hwmon: qpnp-adc: Fix incorrect ADC reads during MPP current sink

MPP2 and MPP4 current sink configuration results in
incorrect ADC readings due to common ground problem
on PM8916.

Fix the issue by using recalibration method if
calibration value found deviated from permitted value.

Change-Id: I1a4065478c00a9819673e1396651d25cb88f527f
Signed-off-by: Dipen Parmar <dipenp@codeaurora.org>