Mode is now handled as a non-inheritable attribute, and CUDADevice & CUDAHost are now handled as inheritable attributes.  In all three cases, this makes the processing behavior more consistent with the declared behavior in Attr.td.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@189532 91177308-0d34-0410-b5e6-96231b3b80d8