Don't consider different C function types to be different representation
Don't consider different C function types to be different representation

This should eventually consider how Clang signs different function pointer types,
but for now, this unblocks progress on targets without ptrauth.

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