hwmon: qpnp-adc-current: Fix specifying batfet status

For the condition when PM8941 is true use the BATFET status
that is passed to the calibration api. Ignore the BATFET
status for all other PMIC versions.

For PM8941 when BATFET is open, the reads on channel 0 for
Internal RSENSE are redirected in HW to channel 0x5:
 EXTRSNS_OFFSET. Recalibrate based on this channel.

Change-Id: Ib0d477c5fb4537379b31faf1676d5956317b06a7
CRs-Fixed: 629758
Signed-off-by: Siddartha Mohanadoss <smohanad@codeaurora.org>