Implement atomic compare exchange and atomic bin OPs for
PPC and s390

Change-Id: I8f89a0ebb912082c4c1e6b9a3daf64f28c114010
Reviewed-on: https://chromium-review.googlesource.com/1013861Reviewed-by: Junliang Yan <jyan@ca.ibm.com>
Commit-Queue: Junliang Yan <jyan@ca.ibm.com>
Cr-Commit-Position: refs/heads/master@{#53165}