[build-script-impl][lto] When compiling swift/llvm with lto, pass LLVM_PARALLEL_LINK_JOBS to swift as well as llvm.
[build-script-impl][lto] When compiling swift/llvm with lto, pass LLVM_PARALLEL_LINK_JOBS to swift as well as llvm.

The reason to do this is the same reason that we already pass in
-DLLVM_ENABLE_LTO=YES to swift, to ensure that parts of our codebase that use
the llvm build machinery (e.g. the unittests) do not use too many linker jobs
given the memory constraints of a given machine.

rdar://24717107

ahoppen/swift,xwu/swift,sschiau/swift,rudkx/swift,karwa/swift,zisko/swift,apple/swift,austinzheng/swift,gmilos/swift,alblue/swift,danielmartin/swift,airspeedswift/swift,devincoughlin/swift,shajrawi/swift,parkera/swift,xedin/swift,benlangmuir/swift,kperryua/swift,tkremenek/swift,airspeedswift/swift,gottesmm/swift,karwa/swift,kperryua/swift,stephentyrone/swift,lorentey/swift,calebd/swift,allevato/swift,practicalswift/swift,Jnosh/swift,deyton/swift,xedin/swift,codestergit/swift,bitjammer/swift,gmilos/swift,jtbandes/swift,glessard/swift,arvedviehweger/swift,allevato/swift,jtbandes/swift,modocache/swift,brentdax/swift,nathawes/swift,IngmarStein/swift,gottesmm/swift,CodaFi/swift,hooman/swift,stephentyrone/swift,jtbandes/swift,jckarter/swift,shajrawi/swift,tkremenek/swift,brentdax/swift,jtbandes/swift,IngmarStein/swift,kstaring/swift,sschiau/swift,brentdax/swift,gregomni/swift,shahmishal/swift,ahoppen/swift,hughbe/swift,manavgabhawala/swift,hooman/swift,xedin/swift,danielmartin/swift,shahmishal/swift,brentdax/swift,codestergit/swift,codestergit/swift,hughbe/swift,Jnosh/swift,JGiola/swift,IngmarStein/swift,apple/swift,gottesmm/swift,ahoppen/swift,amraboelela/swift,frootloops/swift,allevato/swift,atrick/swift,benlangmuir/swift,huonw/swift,amraboelela/swift,frootloops/swift,xedin/swift,kstaring/swift,return/swift,jmgc/swift,gregomni/swift,allevato/swift,practicalswift/swift,JGiola/swift,xwu/swift,shajrawi/swift,sschiau/swift,Jnosh/swift,therealbnut/swift,alblue/swift,jckarter/swift,karwa/swift,frootloops/swift,bitjammer/swift,calebd/swift,rudkx/swift,aschwaighofer/swift,shahmishal/swift,huonw/swift,russbishop/swift,ben-ng/swift,return/swift,harlanhaskins/swift,xwu/swift,jmgc/swift,jckarter/swift,xedin/swift,CodaFi/swift,tardieu/swift,JaSpa/swift,aschwaighofer/swift,huonw/swift,tinysun212/swift-windows,hughbe/swift,gottesmm/swift,shajrawi/swift,devincoughlin/swift,jtbandes/swift,manavgabhawala/swift,russbishop/swift,apple/swift,shajrawi/swift,IngmarStein/swift,austinzheng/swift,tkremenek/swift,karwa/swift,allevato/swift,modocache/swift,roambotics/swift,modocache/swift,russbishop/swift,sschiau/swift,milseman/swift,parkera/swift,return/swift,swiftix/swift,russbishop/swift,zisko/swift,tjw/swift,kperryua/swift,xedin/swift,devincoughlin/swift,manavgabhawala/swift,parkera/swift,tjw/swift,djwbrown/swift,harlanhaskins/swift,frootloops/swift,djwbrown/swift,manavgabhawala/swift,kperryua/swift,danielmartin/swift,swiftix/swift,therealbnut/swift,tjw/swift,gmilos/swift,JaSpa/swift,practicalswift/swift,swiftix/swift,jopamer/swift,manavgabhawala/swift,parkera/swift,tkremenek/swift,atrick/swift,atrick/swift,deyton/swift,felix91gr/swift,stephentyrone/swift,karwa/swift,ben-ng/swift,arvedviehweger/swift,therealbnut/swift,russbishop/swift,kstaring/swift,karwa/swift,amraboelela/swift,stephentyrone/swift,huonw/swift,tinysun212/swift-windows,harlanhaskins/swift,natecook1000/swift,manavgabhawala/swift,arvedviehweger/swift,OscarSwanros/swift,deyton/swift,parkera/swift,jckarter/swift,gregomni/swift,gribozavr/swift,brentdax/swift,bitjammer/swift,shahmishal/swift,natecook1000/swift,bitjammer/swift,sschiau/swift,benlangmuir/swift,glessard/swift,frootloops/swift,nathawes/swift,natecook1000/swift,OscarSwanros/swift,jmgc/swift,lorentey/swift,harlanhaskins/swift,hughbe/swift,shahmishal/swift,karwa/swift,tardieu/swift,felix91gr/swift,kperryua/swift,practicalswift/swift,jopamer/swift,xwu/swift,aschwaighofer/swift,glessard/swift,gmilos/swift,xwu/swift,JGiola/swift,devincoughlin/swift,tardieu/swift,ben-ng/swift,zisko/swift,swiftix/swift,xwu/swift,tjw/swift,harlanhaskins/swift,uasys/swift,calebd/swift,roambotics/swift,uasys/swift,gregomni/swift,hughbe/swift,JaSpa/swift,natecook1000/swift,zisko/swift,harlanhaskins/swift,airspeedswift/swift,shahmishal/swift,gribozavr/swift,uasys/swift,roambotics/swift,natecook1000/swift,return/swift,deyton/swift,arvedviehweger/swift,danielmartin/swift,gottesmm/swift,return/swift,danielmartin/swift,return/swift,rudkx/swift,austinzheng/swift,tardieu/swift,natecook1000/swift,CodaFi/swift,JaSpa/swift,lorentey/swift,djwbrown/swift,deyton/swift,JGiola/swift,uasys/swift,bitjammer/swift,OscarSwanros/swift,allevato/swift,djwbrown/swift,tardieu/swift,jopamer/swift,calebd/swift,austinzheng/swift,kstaring/swift,aschwaighofer/swift,austinzheng/swift,JGiola/swift,ben-ng/swift,shajrawi/swift,natecook1000/swift,deyton/swift,milseman/swift,hooman/swift,deyton/swift,apple/swift,zisko/swift,jopamer/swift,nathawes/swift,gottesmm/swift,jtbandes/swift,Jnosh/swift,CodaFi/swift,danielmartin/swift,milseman/swift,OscarSwanros/swift,nathawes/swift,alblue/swift,uasys/swift,Jnosh/swift,manavgabhawala/swift,nathawes/swift,hughbe/swift,milseman/swift,tjw/swift,lorentey/swift,lorentey/swift,OscarSwanros/swift,djwbrown/swift,kstaring/swift,apple/swift,OscarSwanros/swift,brentdax/swift,stephentyrone/swift,xedin/swift,codestergit/swift,benlangmuir/swift,felix91gr/swift,zisko/swift,milseman/swift,tardieu/swift,rudkx/swift,modocache/swift,alblue/swift,hooman/swift,shajrawi/swift,practicalswift/swift,sschiau/swift,ben-ng/swift,uasys/swift,benlangmuir/swift,kstaring/swift,apple/swift,amraboelela/swift,stephentyrone/swift,glessard/swift,parkera/swift,huonw/swift,jckarter/swift,devincoughlin/swift,airspeedswift/swift,calebd/swift,alblue/swift,sschiau/swift,rudkx/swift,JaSpa/swift,roambotics/swift,calebd/swift,kperryua/swift,jopamer/swift,gribozavr/swift,amraboelela/swift,tjw/swift,russbishop/swift,tkremenek/swift,gregomni/swift,practicalswift/swift,ahoppen/swift,frootloops/swift,lorentey/swift,gribozavr/swift,nathawes/swift,airspeedswift/swift,gmilos/swift,nathawes/swift,devincoughlin/swift,tinysun212/swift-windows,huonw/swift,stephentyrone/swift,calebd/swift,swiftix/swift,frootloops/swift,hooman/swift,modocache/swift,tinysun212/swift-windows,ben-ng/swift,jmgc/swift,alblue/swift,therealbnut/swift,tkremenek/swift,zisko/swift,Jnosh/swift,CodaFi/swift,jmgc/swift,tinysun212/swift-windows,gregomni/swift,gribozavr/swift,roambotics/swift,ahoppen/swift,shajrawi/swift,tjw/swift,arvedviehweger/swift,russbishop/swift,milseman/swift,gribozavr/swift,IngmarStein/swift,austinzheng/swift,atrick/swift,ben-ng/swift,codestergit/swift,felix91gr/swift,CodaFi/swift,atrick/swift,hughbe/swift,IngmarStein/swift,therealbnut/swift,ahoppen/swift,JGiola/swift,austinzheng/swift,devincoughlin/swift,bitjammer/swift,OscarSwanros/swift,practicalswift/swift,amraboelela/swift,huonw/swift,allevato/swift,aschwaighofer/swift,karwa/swift,codestergit/swift,gribozavr/swift,tardieu/swift,sschiau/swift,JaSpa/swift,gottesmm/swift,devincoughlin/swift,codestergit/swift,therealbnut/swift,kperryua/swift,xwu/swift,benlangmuir/swift,tkremenek/swift,modocache/swift,xedin/swift,shahmishal/swift,jopamer/swift,felix91gr/swift,djwbrown/swift,bitjammer/swift,shahmishal/swift,brentdax/swift,gribozavr/swift,glessard/swift,arvedviehweger/swift,roambotics/swift,glessard/swift,lorentey/swift,Jnosh/swift,jtbandes/swift,atrick/swift,tinysun212/swift-windows,parkera/swift,airspeedswift/swift,return/swift,practicalswift/swift,alblue/swift,jmgc/swift,gmilos/swift,therealbnut/swift,hooman/swift,gmilos/swift,jckarter/swift,amraboelela/swift,kstaring/swift,aschwaighofer/swift,rudkx/swift,IngmarStein/swift,CodaFi/swift,airspeedswift/swift,lorentey/swift,jopamer/swift,swiftix/swift,parkera/swift,JaSpa/swift,djwbrown/swift,tinysun212/swift-windows,danielmartin/swift,arvedviehweger/swift,milseman/swift,swiftix/swift,jmgc/swift,hooman/swift,modocache/swift,aschwaighofer/swift,uasys/swift,felix91gr/swift,harlanhaskins/swift,felix91gr/swift,jckarter/swift