Revert r182909.

PR/16177


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@182919 91177308-0d34-0410-b5e6-96231b3b80d8
[SystemZ] Enable unaligned accesses

The code to distinguish between unaligned and aligned addresses was
already there, so this is mostly just a switch-on-and-test process.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@182920 91177308-0d34-0410-b5e6-96231b3b80d8