BatteryService: Add BATTERY_PROPERTY_PART_STATUS.

Add new property from the Health v3 HAL. Note we don't add
BATTERY_PROPERTY_SERIAL_NUMBER since it's not an integer and doesn't fit
in nicely with the existing getProperty API in BatteryMonitor.h.

Bug: 309792384
Test: m
Change-Id: Id05265f3e355396f0673bfac38b3460eb2d34f8b