Use stage1 build variables when building the RTS
Use stage1 build variables when building the RTS

The fourth argument of distdir-way-opts was missing. So, for example,
SRC_HC_OPTS_STAGE1 was not used when building the RTS.

Test Plan: validate --slow

Reviewers: austin, bgamari, thomie

Reviewed By: thomie

Differential Revision: https://phabricator.haskell.org/D1857

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