[media] media: i2c: add driver for dual LED Flash, lm3560

[media] media: i2c: add driver for dual LED Flash, lm3560

Adds the driver for the LM3560, dual LED Flash The LM3560 has two 1A
constant current driver for high current white LEDs.

It is controlled via an I2C compatible interface(up to 400kHz).

Each flash brightness, torch  brightness and enable/disable can be
controlled independantly, but flash timeout and operation mode are shared.

Signed-off-by: Daniel Jeong <gshark.jeong@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>