input: sensor: fix mpu3050 not connected due to power logic error

The power management logic was not correctly handled and caused
the sensor chip in the wrong state. Fix this issue by add some
restrictions to the runtime power management usage counter.

Change-Id: Ib456137190c295491443b6eadbc4cfbb409b3457
Signed-off-by: Oliver Wang <mengmeng@codeaurora.org>