power: bcl_peripheral: Recalibrate BCL after FG switch current sensing

There is a race condition in software between when
the BCL driver reads the gain/offset registers for
BCL adc calibration and when fuel gauge decides
whether to use internal or external current sensing.
This can cause the BCL driver to load the gain/offset
for the wrong channel if the fuel gauge changes the
current sensing registers after the BCL. This patch
address this issue by recalibrating BCL after fuel
gauge makes the switch.

Change-Id: Id0d182d750e6a57a3545179b7c1d4dc1f44a6200
Signed-off-by: Shiju Mathew <shijum@codeaurora.org>