power_supply: Add watchdog and safety timer expiries under PROP_HEALTH_*

As most of the charger chips come with two kinds of safety features
related to timing:

1. Watchdog Timer (interms of seconds/mins)
2. Safety Timer (interms of hours)

This patch adds these to fault causes in POWER_SUPPLY_PROP_HEALTH_* enums
so that whenever there is either watchdog timeout or safety timer timeout
driver could notify the user space accurately about the fault and will
also be helpful for debug.

Signed-off-by: Ramakrishna Pallala <ramakrishna.pallala@intel.com>
Signed-off-by: Anton Vorontsov <anton@enomsg.org>