[ARM64] Add RUN lines for "–target arm64 –mattr=-fp-armv8" on AArch64 no-fp test.

[ARM64] Add RUN lines for "–target arm64 –mattr=-fp-armv8" on AArch64 no-fp test.

This patch is a supplement of implementing predicate of FP, enabling aarch64 backend
no-fp tests on arm64 target for verification. During this, one bug is exposed and
fixed by this patch.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207215 91177308-0d34-0410-b5e6-96231b3b80d8