msm: camera: Add a driver to control IR LED device

This driver is able to control a IR LED device. The interface to
user space is:
CFG_IR_LED_INIT
CFG_IR_LED_OFF
CFG_IR_LED_ON with intensity field
CFG_IR_LED_RELEASE.

Change-Id: I2e04fa47efd1454bb487eca67bd9ceaeab3e9edf
Signed-off-by: Vivek Veenam <vveenam@codeaurora.org>