[tools] Fix a const cast warning in swift-stdlib-tool.
[tools] Fix a const cast warning in swift-stdlib-tool.

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