In order to prepare for checking RTC failure in the early boot
paths move the rtc failure calculation to pmutil.c and add a helper
function to determine if failure occurred.
BUG=b:63054105
Change-Id: I1d90cc557225ddbba1787bf95eae0de623af487e
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: https://review.coreboot.org/21555
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Furquan Shaikh <furquan@google.com>