[cxx-interop] Skip void types in emitCXXConstructorThunkIfNeeded.
[cxx-interop] Skip void types in emitCXXConstructorThunkIfNeeded.

emitCXXConstructorThunkIfNeeded receives a SIL function that may contain
metatypes. If so, they will be converted to void and we need to skip
them when emitting the thunk's args.

tkremenek/swift,jmgc/swift,jmgc/swift,ahoppen/swift,rudkx/swift,apple/swift,jmgc/swift,JGiola/swift,apple/swift,glessard/swift,hooman/swift,hooman/swift,parkera/swift,rudkx/swift,gregomni/swift,xwu/swift,xwu/swift,glessard/swift,hooman/swift,jmgc/swift,roambotics/swift,gregomni/swift,glessard/swift,rudkx/swift,atrick/swift,rudkx/swift,glessard/swift,tkremenek/swift,parkera/swift,atrick/swift,apple/swift,gregomni/swift,rudkx/swift,apple/swift,jmgc/swift,ahoppen/swift,gregomni/swift,parkera/swift,roambotics/swift,parkera/swift,JGiola/swift,gregomni/swift,benlangmuir/swift,parkera/swift,ahoppen/swift,rudkx/swift,tkremenek/swift,jmgc/swift,ahoppen/swift,hooman/swift,tkremenek/swift,benlangmuir/swift,benlangmuir/swift,ahoppen/swift,xwu/swift,benlangmuir/swift,glessard/swift,tkremenek/swift,parkera/swift,JGiola/swift,hooman/swift,atrick/swift,hooman/swift,JGiola/swift,parkera/swift,tkremenek/swift,atrick/swift,atrick/swift,xwu/swift,xwu/swift,roambotics/swift,parkera/swift,tkremenek/swift,apple/swift,benlangmuir/swift,roambotics/swift,atrick/swift,roambotics/swift,roambotics/swift,benlangmuir/swift,gregomni/swift,xwu/swift,JGiola/swift,jmgc/swift,hooman/swift,glessard/swift,apple/swift,ahoppen/swift,JGiola/swift,xwu/swift