[AArch64]The compare to zero intrinsics should be implemented by 'icmp/fcmp' and 'sext' not 'zext'. Modify the implementation by replacing zext with sext.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@197898 91177308-0d34-0410-b5e6-96231b3b80d8