We only need it for MAX_ERRNO, and it's time we had somewhere to put the little assembler utility macros we've been putting off writing. Change-Id: I9354d2e0dc47c689296a34b5b229fc9ba75f1a83
No non-comment changes to the .S files. Change-Id: Iafcfd004c3ea92b64268f80ab16df615b97cefac
(cherry-pick of 04c0ac14a49e0969333008a9522b64046d58fbdc.) Change-Id: I06d0b6c2a8781602362b81f48faf1cca76b9ec05