AArch64: Cleanup CCMP code; NFC
AArch64: Cleanup CCMP code; NFC

Cleanup CCMP pattern matching code in preparation for review/bugfix:
- Rename `isConjunctionDisjunctionTree()` to `canEmitConjunction()`
  (it won't accept arbitrary disjunctions and is really about whether we
   can transform the subtree into a conjunction that we can emit).
- Rename `emitConjunctionDisjunctionTree()` to `emitConjunction()`

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@346203 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,apple/swift-llvm,llvm-mirror/llvm,apple/swift-llvm,apple/swift-llvm,llvm-mirror/llvm,apple/swift-llvm,llvm-mirror/llvm,llvm-mirror/llvm,llvm-mirror/llvm,apple/swift-llvm,apple/swift-llvm,llvm-mirror/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,llvm-mirror/llvm,apple/swift-llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,apple/swift-llvm,llvm-mirror/llvm