[AArch64 NEON] Lower SELECT_CC with vector operand.

When the scalar compare is between floating point and operands are
vector, we custom lower SELECT_CC to use NEON SIMD compare for
generating less instructions.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200365 91177308-0d34-0410-b5e6-96231b3b80d8