Replace structure member "level" in power_signal_info with "flags".
"level" has been used on all boards to indicate active-high or
active-low levels. Addition of "flags" allows easy extension of
power_signal_info structure to define various flags that might be
applicable to power signals (e.g. "level"). Going forward, additional
flag will be added in follow-up CLs.
Also, provide a helper function power_signal_is_asserted that checks
the actual level of a signal and compares it to the flags level to
identify if a power signal is asserted.
BUG=b:65421825
BRANCH=None
TEST=make -j buildall
Change-Id: Iacaabd1185b347c17b5159f05520731505b824b8
Signed-off-by: Furquan Shaikh <furquan@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/679979
Reviewed-by: Nicolas Boichat <drinkcat@chromium.org>