AMDGPU/Docs: Make target naming consistent

  - R600 Arch: Use Radeon HD XXXX Series
  - GCN Arch: Use GFXX

Differential Revision: https://reviews.llvm.org/D39019


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@316100 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed