This patch is to update pr61315.ll what was needed as part of
D146632 and caused build failures.
Reviewed By: stefanp
Differential Revision: https://reviews.llvm.org/D147675
This DAG combine is correct on little endian targets but
is incorrect on big endian targets.
Add big endian code to correct it.
Differential revision: https://reviews.llvm.org/D146460