Guybrush: Sleep the battery fuel gauge before hibernating
Guybrush: Sleep the battery fuel gauge before hibernating

Before we go into hibernate, try to put the battery fuel gauge into
sleep mode.  Note we must be in a low current state for the gauge to
actually enter this mode.

BRANCH=None
BUG=b:186774653
TEST=on guybrush, observe power reduction in Z5

Signed-off-by: Diana Z <cb2016afc7183e5356c690dc63b4ba817470501a@chromium.org>
Change-Id: Ie02aa3ede1b3a89592bdd5cd8e701887db3c2d9f
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2967039
Reviewed-by: Aseda Aboagye <12c9b286316a940fd31c24070da5ab64cdd4d0e7@chromium.org>

coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec