AMDGPU/SI: Refactor VOP[12C] tablegen definitions

Summary:
Pass the VOPProfile object all the through to *_m multiclasses.  This will
allow us to do more simplifications in the future.

Reviewers: arsenm

Subscribers: arsenm, llvm-commits

Differential Revision: http://reviews.llvm.org/D13437

llvm-svn: 252339