Make SOC scaling offset for shutdown configurable

Modify the SOC scaling offset for shutdown so that user can set the
value per a product device tree and also update that value during
runtime. This makes it easy for developers to customize behavior and
test full charge / discharge cycling.

Bug: 284989176
Test: Adjust google,soc_shutdown_offset or
  /sys/class/power_supply/sw5100_bms/soc_shutdown_offset
Signed-off-by: Brandon Edens <[email protected]>
(cherry picked from https://partner-android-review.googlesource.com/q/commit:232c7e93f9a2f4c613842395074a2c6683a777f9)
Merged-In: I9e1b4c1b3bc11bfeaa01b317bf90594988573a37
Change-Id: I9e1b4c1b3bc11bfeaa01b317bf90594988573a37
1 file changed