AA: Use generic intrinsics for tests instead of target specific ones

AA: Use generic intrinsics for tests instead of target specific ones

Update a few tests to use llvm.masked.load/store instead of arm neon
vector loads and stores, and move the tests that are actually specific
to those arm intrinsics to their own files. This lets us mark the
tests that use target specific intrinsics as requiring those targets.

llvm-svn: 302972