docs: update Windows build documentation for clang
docs: update Windows build documentation for clang

Avoid using a junction when building the llvm/clang tools.  Prefer to use the LLVM projects support instead.
nathawes/swift,xedin/swift,roambotics/swift,karwa/swift,ahoppen/swift,amraboelela/swift,ahoppen/swift,practicalswift/swift,atrick/swift,jmgc/swift,JGiola/swift,karwa/swift,devincoughlin/swift,allevato/swift,rudkx/swift,karwa/swift,jmgc/swift,parkera/swift,austinzheng/swift,CodaFi/swift,jckarter/swift,gregomni/swift,lorentey/swift,austinzheng/swift,aschwaighofer/swift,airspeedswift/swift,roambotics/swift,nathawes/swift,tkremenek/swift,benlangmuir/swift,nathawes/swift,roambotics/swift,ahoppen/swift,ahoppen/swift,CodaFi/swift,amraboelela/swift,xwu/swift,allevato/swift,aschwaighofer/swift,stephentyrone/swift,airspeedswift/swift,apple/swift,stephentyrone/swift,jckarter/swift,austinzheng/swift,gribozavr/swift,JGiola/swift,aschwaighofer/swift,jmgc/swift,shajrawi/swift,aschwaighofer/swift,allevato/swift,gregomni/swift,karwa/swift,CodaFi/swift,apple/swift,hooman/swift,karwa/swift,austinzheng/swift,gribozavr/swift,xedin/swift,glessard/swift,lorentey/swift,sschiau/swift,practicalswift/swift,hooman/swift,atrick/swift,shajrawi/swift,xedin/swift,airspeedswift/swift,CodaFi/swift,gregomni/swift,jckarter/swift,devincoughlin/swift,tkremenek/swift,apple/swift,airspeedswift/swift,roambotics/swift,gribozavr/swift,hooman/swift,xwu/swift,danielmartin/swift,hooman/swift,gribozavr/swift,amraboelela/swift,CodaFi/swift,devincoughlin/swift,stephentyrone/swift,lorentey/swift,tkremenek/swift,jmgc/swift,xedin/swift,nathawes/swift,devincoughlin/swift,nathawes/swift,allevato/swift,stephentyrone/swift,shajrawi/swift,devincoughlin/swift,benlangmuir/swift,jmgc/swift,sschiau/swift,rudkx/swift,austinzheng/swift,parkera/swift,glessard/swift,parkera/swift,lorentey/swift,austinzheng/swift,shahmishal/swift,CodaFi/swift,tkremenek/swift,stephentyrone/swift,nathawes/swift,airspeedswift/swift,glessard/swift,hooman/swift,roambotics/swift,parkera/swift,apple/swift,amraboelela/swift,hooman/swift,xedin/swift,jckarter/swift,JGiola/swift,austinzheng/swift,atrick/swift,xwu/swift,gregomni/swift,lorentey/swift,shajrawi/swift,atrick/swift,xedin/swift,sschiau/swift,gribozavr/swift,aschwaighofer/swift,practicalswift/swift,shajrawi/swift,roambotics/swift,rudkx/swift,tkremenek/swift,hooman/swift,jmgc/swift,ahoppen/swift,CodaFi/swift,benlangmuir/swift,JGiola/swift,rudkx/swift,shahmishal/swift,jckarter/swift,sschiau/swift,aschwaighofer/swift,benlangmuir/swift,gribozavr/swift,karwa/swift,apple/swift,apple/swift,practicalswift/swift,danielmartin/swift,glessard/swift,xwu/swift,rudkx/swift,glessard/swift,benlangmuir/swift,danielmartin/swift,allevato/swift,atrick/swift,harlanhaskins/swift,gregomni/swift,shahmishal/swift,devincoughlin/swift,sschiau/swift,harlanhaskins/swift,harlanhaskins/swift,rudkx/swift,shahmishal/swift,practicalswift/swift,xedin/swift,tkremenek/swift,danielmartin/swift,practicalswift/swift,shahmishal/swift,glessard/swift,jckarter/swift,jckarter/swift,danielmartin/swift,shahmishal/swift,aschwaighofer/swift,sschiau/swift,sschiau/swift,devincoughlin/swift,airspeedswift/swift,gribozavr/swift,amraboelela/swift,parkera/swift,shajrawi/swift,allevato/swift,allevato/swift,practicalswift/swift,xedin/swift,parkera/swift,shahmishal/swift,shahmishal/swift,gribozavr/swift,shajrawi/swift,harlanhaskins/swift,xwu/swift,karwa/swift,amraboelela/swift,JGiola/swift,tkremenek/swift,shajrawi/swift,xwu/swift,harlanhaskins/swift,practicalswift/swift,gregomni/swift,amraboelela/swift,lorentey/swift,xwu/swift,stephentyrone/swift,parkera/swift,airspeedswift/swift,stephentyrone/swift,atrick/swift,ahoppen/swift,karwa/swift,danielmartin/swift,lorentey/swift,harlanhaskins/swift,benlangmuir/swift,jmgc/swift,parkera/swift,lorentey/swift,JGiola/swift,sschiau/swift,harlanhaskins/swift,danielmartin/swift,devincoughlin/swift,nathawes/swift