msm: camera: Modified Average mode to Addition mode for IMX074

Modified the driver code to change from Average mode to Addition mode
settings to compensate more linecount and lessgain for IMX074 sensor.

Change-Id: Idd7d202ec0615ee39489fed1c07d40a6471ac094
Signed-off-by: Sampath Kumar Matheswaran <csmathe@codeaurora.org>