msm: camera: Return current lens position in actuator driver

Actuator user space driver requires lens position after move focus
call returns. Return lens position as part cfg params for move focus
ioctl.

Change-Id: Ie684e898959a8edfd2a919b69d4607497b998ac4
Signed-off-by: Sreesudhan Ramakrish Ramkumar <srramku@codeaurora.org>