[SystemZ] Mark CTTZ_ZERO_UNDEF/CTLZ_ZERO_UNDEF as Expand instead of Custom since the custom logic just did what Expand does when CTTZ/CTLZ are Legal. NFC

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@267109 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed