SILOptimizer: rename `cdecl` to `ctor` (NFC)
SILOptimizer: rename `cdecl` to `ctor` (NFC)

`cdecl` is a keyword in the non-conforming C++ dialect used on Windows
which expands to `__cdecl`.  Simply rename the variable to avoid the
replacement.  Although it is possible to `#undef cdecl`, renaming makes
it less confusing for non-Windows developers.

roambotics/swift,xwu/swift,benlangmuir/swift,hooman/swift,karwa/swift,rudkx/swift,devincoughlin/swift,nathawes/swift,jmgc/swift,airspeedswift/swift,benlangmuir/swift,airspeedswift/swift,gribozavr/swift,tkremenek/swift,CodaFi/swift,harlanhaskins/swift,CodaFi/swift,tkremenek/swift,JGiola/swift,karwa/swift,allevato/swift,harlanhaskins/swift,nathawes/swift,gribozavr/swift,hooman/swift,glessard/swift,nathawes/swift,aschwaighofer/swift,devincoughlin/swift,aschwaighofer/swift,xwu/swift,aschwaighofer/swift,CodaFi/swift,jmgc/swift,lorentey/swift,parkera/swift,stephentyrone/swift,jmgc/swift,nathawes/swift,apple/swift,glessard/swift,stephentyrone/swift,harlanhaskins/swift,gribozavr/swift,apple/swift,tkremenek/swift,rudkx/swift,atrick/swift,CodaFi/swift,stephentyrone/swift,atrick/swift,harlanhaskins/swift,CodaFi/swift,aschwaighofer/swift,parkera/swift,aschwaighofer/swift,sschiau/swift,aschwaighofer/swift,tkremenek/swift,ahoppen/swift,jckarter/swift,roambotics/swift,xwu/swift,atrick/swift,stephentyrone/swift,hooman/swift,xwu/swift,allevato/swift,lorentey/swift,xwu/swift,benlangmuir/swift,allevato/swift,ahoppen/swift,allevato/swift,harlanhaskins/swift,tkremenek/swift,devincoughlin/swift,lorentey/swift,airspeedswift/swift,roambotics/swift,JGiola/swift,jckarter/swift,glessard/swift,sschiau/swift,xwu/swift,gregomni/swift,jckarter/swift,atrick/swift,jmgc/swift,gregomni/swift,devincoughlin/swift,devincoughlin/swift,sschiau/swift,atrick/swift,jmgc/swift,devincoughlin/swift,jmgc/swift,gregomni/swift,glessard/swift,sschiau/swift,sschiau/swift,apple/swift,parkera/swift,lorentey/swift,apple/swift,stephentyrone/swift,lorentey/swift,gribozavr/swift,glessard/swift,airspeedswift/swift,jmgc/swift,rudkx/swift,karwa/swift,karwa/swift,karwa/swift,sschiau/swift,sschiau/swift,CodaFi/swift,apple/swift,JGiola/swift,roambotics/swift,nathawes/swift,JGiola/swift,gregomni/swift,jckarter/swift,allevato/swift,stephentyrone/swift,sschiau/swift,airspeedswift/swift,benlangmuir/swift,harlanhaskins/swift,allevato/swift,atrick/swift,JGiola/swift,nathawes/swift,ahoppen/swift,parkera/swift,hooman/swift,stephentyrone/swift,devincoughlin/swift,roambotics/swift,gribozavr/swift,ahoppen/swift,parkera/swift,parkera/swift,hooman/swift,tkremenek/swift,gregomni/swift,gribozavr/swift,parkera/swift,parkera/swift,gribozavr/swift,karwa/swift,karwa/swift,rudkx/swift,allevato/swift,rudkx/swift,benlangmuir/swift,gribozavr/swift,jckarter/swift,lorentey/swift,xwu/swift,roambotics/swift,hooman/swift,lorentey/swift,glessard/swift,ahoppen/swift,ahoppen/swift,harlanhaskins/swift,CodaFi/swift,karwa/swift,hooman/swift,jckarter/swift,benlangmuir/swift,lorentey/swift,nathawes/swift,devincoughlin/swift,jckarter/swift,gregomni/swift,apple/swift,airspeedswift/swift,aschwaighofer/swift,airspeedswift/swift,tkremenek/swift,rudkx/swift,JGiola/swift