lit.cfg: move the DYLD_LIBRARY_PATH setting code to the config.substitutions
lit.cfg: move the DYLD_LIBRARY_PATH setting code to the config.substitutions

This change the order the configuration file to something that makes more sense: the platform_module_dir value was being set in the middle of the config.substitutions phase.
We needed said value for setting the DYLD_LIBRARY_PATH, so that code was added right after it.

The problem is that by that time config.substitutions.append(('%target-run', config.target_run)) has already happened for local targets

This change moves all said code to just before the substitutions phase, much cleaner and resolves rdar://problem/49835064

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