AMDGPU: Add missing ISA versions gfx7.x.x and 8.x.x.
AMDGPU: Add missing ISA versions gfx7.x.x and 8.x.x.

Patch by Laurent Morichetti.

Differential Revision: https://reviews.llvm.org/D25920

git-svn-id: ffe668792ed300d6c2daa1f6eba2e0aa28d7ec6c@285211 91177308-0d34-0410-b5e6-96231b3b80d8

apple/swift-clang,llvm-mirror/clang,llvm-mirror/clang,llvm-mirror/clang,llvm-mirror/clang,apple/swift-clang,apple/swift-clang,llvm-mirror/clang,apple/swift-clang,apple/swift-clang,apple/swift-clang,llvm-mirror/clang,llvm-mirror/clang,apple/swift-clang,apple/swift-clang,llvm-mirror/clang,llvm-mirror/clang,apple/swift-clang,apple/swift-clang,llvm-mirror/clang