AMDGPU: Add support for isa version note

  - Emit NT_AMD_AMDGPU_ISA
  - Add assembler parsing for isa version directive
    - If isa version directive does not match command line arguments, then return error

Differential Revision: https://reviews.llvm.org/D38748


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@315808 91177308-0d34-0410-b5e6-96231b3b80d8
10 files changed