power: pm8921-charger: various apis

Implement API's to
	- set maximum battery charging current
	- disable drawing current from the source
	- detect if battery is being charged and which charger source
	  is charging the battery
	- get battery temperature
	- detect battery is present
	- detect usb is present
	- detect dc is present
	- set max trickle charging time
	- set max auto charging time

Signed-off-by: Abhijeet Dharmapurikar <adharmap@codeaurora.org>
3 files changed