utils: add CMake to Linux checkout
utils: add CMake to Linux checkout

In order to prepare for a migration to CMake 3.15 to enable the use of
the new Swift support, we will add a build of CMake for Linux to ease
the transition.  This adds CMake to the checkout on Linux.

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