IRGen: Rename emitInitializeMetadata() to emitInitializeValueMetadata()
IRGen: Rename emitInitializeMetadata() to emitInitializeValueMetadata()

Small cleanup suggested by John in review.

amraboelela/swift,karwa/swift,gribozavr/swift,danielmartin/swift,austinzheng/swift,stephentyrone/swift,shajrawi/swift,nathawes/swift,brentdax/swift,xwu/swift,apple/swift,karwa/swift,gribozavr/swift,shajrawi/swift,sschiau/swift,practicalswift/swift,austinzheng/swift,stephentyrone/swift,allevato/swift,benlangmuir/swift,brentdax/swift,amraboelela/swift,danielmartin/swift,shahmishal/swift,gregomni/swift,rudkx/swift,atrick/swift,gribozavr/swift,hooman/swift,devincoughlin/swift,airspeedswift/swift,CodaFi/swift,shajrawi/swift,ahoppen/swift,jmgc/swift,JGiola/swift,rudkx/swift,CodaFi/swift,nathawes/swift,parkera/swift,jckarter/swift,lorentey/swift,jckarter/swift,gribozavr/swift,xwu/swift,parkera/swift,roambotics/swift,apple/swift,atrick/swift,karwa/swift,apple/swift,allevato/swift,tkremenek/swift,CodaFi/swift,roambotics/swift,devincoughlin/swift,rudkx/swift,hooman/swift,shahmishal/swift,parkera/swift,jmgc/swift,JGiola/swift,shahmishal/swift,amraboelela/swift,benlangmuir/swift,gregomni/swift,sschiau/swift,devincoughlin/swift,devincoughlin/swift,ahoppen/swift,stephentyrone/swift,lorentey/swift,tkremenek/swift,CodaFi/swift,austinzheng/swift,sschiau/swift,alblue/swift,practicalswift/swift,hooman/swift,shahmishal/swift,benlangmuir/swift,lorentey/swift,lorentey/swift,danielmartin/swift,xedin/swift,karwa/swift,jckarter/swift,allevato/swift,gribozavr/swift,hooman/swift,JGiola/swift,shajrawi/swift,atrick/swift,amraboelela/swift,parkera/swift,alblue/swift,allevato/swift,benlangmuir/swift,apple/swift,practicalswift/swift,shahmishal/swift,apple/swift,devincoughlin/swift,natecook1000/swift,austinzheng/swift,brentdax/swift,hooman/swift,aschwaighofer/swift,lorentey/swift,sschiau/swift,xedin/swift,alblue/swift,stephentyrone/swift,aschwaighofer/swift,jmgc/swift,ahoppen/swift,practicalswift/swift,ahoppen/swift,brentdax/swift,lorentey/swift,danielmartin/swift,parkera/swift,hooman/swift,harlanhaskins/swift,natecook1000/swift,danielmartin/swift,austinzheng/swift,tkremenek/swift,xwu/swift,practicalswift/swift,xedin/swift,gregomni/swift,harlanhaskins/swift,gregomni/swift,alblue/swift,tkremenek/swift,shajrawi/swift,nathawes/swift,jckarter/swift,harlanhaskins/swift,devincoughlin/swift,JGiola/swift,rudkx/swift,glessard/swift,harlanhaskins/swift,atrick/swift,jckarter/swift,gregomni/swift,tkremenek/swift,amraboelela/swift,xedin/swift,aschwaighofer/swift,brentdax/swift,brentdax/swift,tkremenek/swift,atrick/swift,harlanhaskins/swift,benlangmuir/swift,natecook1000/swift,practicalswift/swift,allevato/swift,natecook1000/swift,brentdax/swift,jckarter/swift,gregomni/swift,practicalswift/swift,karwa/swift,nathawes/swift,harlanhaskins/swift,CodaFi/swift,lorentey/swift,lorentey/swift,glessard/swift,jmgc/swift,xwu/swift,stephentyrone/swift,xedin/swift,aschwaighofer/swift,amraboelela/swift,roambotics/swift,xwu/swift,tkremenek/swift,glessard/swift,glessard/swift,stephentyrone/swift,benlangmuir/swift,airspeedswift/swift,atrick/swift,shahmishal/swift,natecook1000/swift,parkera/swift,shajrawi/swift,nathawes/swift,roambotics/swift,roambotics/swift,xedin/swift,parkera/swift,amraboelela/swift,austinzheng/swift,harlanhaskins/swift,sschiau/swift,roambotics/swift,shahmishal/swift,devincoughlin/swift,karwa/swift,airspeedswift/swift,airspeedswift/swift,aschwaighofer/swift,shajrawi/swift,apple/swift,jmgc/swift,gribozavr/swift,austinzheng/swift,CodaFi/swift,JGiola/swift,ahoppen/swift,allevato/swift,airspeedswift/swift,CodaFi/swift,nathawes/swift,ahoppen/swift,practicalswift/swift,karwa/swift,JGiola/swift,sschiau/swift,allevato/swift,airspeedswift/swift,karwa/swift,aschwaighofer/swift,jmgc/swift,alblue/swift,gribozavr/swift,nathawes/swift,hooman/swift,airspeedswift/swift,rudkx/swift,jmgc/swift,danielmartin/swift,devincoughlin/swift,gribozavr/swift,danielmartin/swift,sschiau/swift,natecook1000/swift,xwu/swift,parkera/swift,rudkx/swift,xwu/swift,stephentyrone/swift,glessard/swift,alblue/swift,jckarter/swift,shajrawi/swift,glessard/swift,natecook1000/swift,xedin/swift,shahmishal/swift,aschwaighofer/swift,alblue/swift,sschiau/swift,xedin/swift