power: vm-bms: Process BMS data during suspend

There could be valid BMS data while going to suspend.
Store this data while entering suspend and process it
in resume. The data is rejected if a new OCV is generated
while suspended.

This fixes the scenarios where the device enters/exists
suspend/resume within the FIFO done IRQ timeline.

CRs-Fixed: 644991
Change-Id: I07b783782d78b61c522492d0d05b67d963411b4d
Signed-off-by: Anirudh Ghayal <aghayal@codeaurora.org>