R600: Pass MCSubtargetInfo reference to R600CodeEmitter

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@182112 91177308-0d34-0410-b5e6-96231b3b80d8
R600: Fix encoding for R600 family GPUs

Reviewed-by: Vincent Lejeune <vljn@ovi.com>

https://bugs.freedesktop.org/show_bug.cgi?id=64193
https://bugs.freedesktop.org/show_bug.cgi?id=64257
https://bugs.freedesktop.org/show_bug.cgi?id=64320

NOTE: This is a candidate for the 3.3 branch.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@182113 91177308-0d34-0410-b5e6-96231b3b80d8