[Hexagon] Give a predicate function a more meaningful name

Change "orisadd" to "IsOrAdd" to follow the naming conventions, and
change "isOrAdd" in the C++ code to "isOrEquivalentToAdd".


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@286886 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed