Libdw: Fix initial register collection on i386
Libdw: Fix initial register collection on i386

RIP-relative addressing isn't available on i386.

snoyberg/ghc,sgillespie/ghc,oldmanmike/ghc,sdiehl/ghc,sdiehl/ghc,oldmanmike/ghc,vTurbine/ghc,sgillespie/ghc,nushio3/ghc,mettekou/ghc,mcschroeder/ghc,ezyang/ghc,snoyberg/ghc,tjakway/ghcjvm,olsner/ghc,olsner/ghc,snoyberg/ghc,mettekou/ghc,mettekou/ghc,vikraman/ghc,mettekou/ghc,nushio3/ghc,ezyang/ghc,nushio3/ghc,ezyang/ghc,shlevy/ghc,GaloisInc/halvm-ghc,GaloisInc/halvm-ghc,nushio3/ghc,sgillespie/ghc,olsner/ghc,tjakway/ghcjvm,oldmanmike/ghc,gridaphobe/ghc,mcschroeder/ghc,gridaphobe/ghc,snoyberg/ghc,vTurbine/ghc,tjakway/ghcjvm,shlevy/ghc,vTurbine/ghc,GaloisInc/halvm-ghc,oldmanmike/ghc,GaloisInc/halvm-ghc,olsner/ghc,GaloisInc/halvm-ghc,olsner/ghc,sdiehl/ghc,sgillespie/ghc,sgillespie/ghc,snoyberg/ghc,GaloisInc/halvm-ghc,tjakway/ghcjvm,vikraman/ghc,tjakway/ghcjvm,mcschroeder/ghc,shlevy/ghc,mettekou/ghc,vTurbine/ghc,gridaphobe/ghc,snoyberg/ghc,gridaphobe/ghc,tjakway/ghcjvm,nushio3/ghc,mcschroeder/ghc,shlevy/ghc,mcschroeder/ghc,shlevy/ghc,vikraman/ghc,vikraman/ghc,sdiehl/ghc,shlevy/ghc,vikraman/ghc,oldmanmike/ghc,GaloisInc/halvm-ghc,oldmanmike/ghc,sdiehl/ghc,snoyberg/ghc,sgillespie/ghc,ezyang/ghc,vTurbine/ghc,sgillespie/ghc,mcschroeder/ghc,ezyang/ghc,vikraman/ghc,gridaphobe/ghc,mettekou/ghc,olsner/ghc,ezyang/ghc,sdiehl/ghc,tjakway/ghcjvm,shlevy/ghc,sdiehl/ghc,nushio3/ghc,ezyang/ghc,gridaphobe/ghc,mettekou/ghc,vTurbine/ghc,gridaphobe/ghc,vikraman/ghc,olsner/ghc,vTurbine/ghc,oldmanmike/ghc,mcschroeder/ghc,nushio3/ghc