msm: camera: Add LED flash support for 8916 Camera.

Driver changes for I2C based DUAL LED flash for 8916 camera.
This flash is available on MTP and also IMX135
on IKKI sensor board.

Change-Id: I04f54e052bf84b1743b5a991e9b10ffccb681156
Signed-off-by: Shankar Ravi <rshankar@codeaurora.org>