[build-script] Teach cross-compile hosts check about --skip-local-build (#27911)
[build-script] Teach cross-compile hosts check about --skip-local-build (#27911)

Check whether there are any cross compile hosts by looking at the
CROSS_COMPILE_HOSTS array, not at ALL_HOSTS, as these can be different
due to --skip-local-build.
airspeedswift/swift,atrick/swift,karwa/swift,parkera/swift,aschwaighofer/swift,CodaFi/swift,xwu/swift,stephentyrone/swift,benlangmuir/swift,karwa/swift,JGiola/swift,allevato/swift,hooman/swift,jmgc/swift,parkera/swift,lorentey/swift,gribozavr/swift,rudkx/swift,gregomni/swift,glessard/swift,atrick/swift,jckarter/swift,lorentey/swift,ahoppen/swift,airspeedswift/swift,aschwaighofer/swift,atrick/swift,gregomni/swift,harlanhaskins/swift,aschwaighofer/swift,gribozavr/swift,jckarter/swift,benlangmuir/swift,tkremenek/swift,parkera/swift,JGiola/swift,roambotics/swift,xwu/swift,airspeedswift/swift,atrick/swift,jmgc/swift,allevato/swift,gribozavr/swift,aschwaighofer/swift,nathawes/swift,karwa/swift,allevato/swift,rudkx/swift,apple/swift,stephentyrone/swift,roambotics/swift,gribozavr/swift,lorentey/swift,lorentey/swift,CodaFi/swift,CodaFi/swift,apple/swift,roambotics/swift,jckarter/swift,lorentey/swift,airspeedswift/swift,ahoppen/swift,lorentey/swift,airspeedswift/swift,CodaFi/swift,allevato/swift,stephentyrone/swift,karwa/swift,parkera/swift,roambotics/swift,harlanhaskins/swift,tkremenek/swift,gribozavr/swift,stephentyrone/swift,hooman/swift,rudkx/swift,parkera/swift,glessard/swift,karwa/swift,tkremenek/swift,xwu/swift,gribozavr/swift,nathawes/swift,apple/swift,tkremenek/swift,gribozavr/swift,CodaFi/swift,gregomni/swift,stephentyrone/swift,harlanhaskins/swift,karwa/swift,jckarter/swift,xwu/swift,harlanhaskins/swift,harlanhaskins/swift,hooman/swift,nathawes/swift,parkera/swift,aschwaighofer/swift,gregomni/swift,parkera/swift,benlangmuir/swift,jmgc/swift,atrick/swift,glessard/swift,lorentey/swift,nathawes/swift,nathawes/swift,allevato/swift,airspeedswift/swift,JGiola/swift,karwa/swift,gribozavr/swift,hooman/swift,tkremenek/swift,jmgc/swift,stephentyrone/swift,apple/swift,glessard/swift,glessard/swift,rudkx/swift,tkremenek/swift,rudkx/swift,roambotics/swift,allevato/swift,glessard/swift,tkremenek/swift,allevato/swift,CodaFi/swift,aschwaighofer/swift,lorentey/swift,parkera/swift,ahoppen/swift,stephentyrone/swift,xwu/swift,hooman/swift,ahoppen/swift,jckarter/swift,xwu/swift,jmgc/swift,jckarter/swift,benlangmuir/swift,nathawes/swift,nathawes/swift,apple/swift,jmgc/swift,benlangmuir/swift,JGiola/swift,ahoppen/swift,ahoppen/swift,karwa/swift,jmgc/swift,harlanhaskins/swift,aschwaighofer/swift,jckarter/swift,xwu/swift,atrick/swift,roambotics/swift,CodaFi/swift,apple/swift,JGiola/swift,hooman/swift,rudkx/swift,JGiola/swift,gregomni/swift,airspeedswift/swift,harlanhaskins/swift,gregomni/swift,benlangmuir/swift,hooman/swift