msm: camera: Support for 1Mhz I2C speed

For custom I2C camera device is need 1Mhz clock.
Currently supported I2C speeds are 100Khz and 400Khz.
For 1Mhz we can change CCI source clock because we
can not able to come up all I2C speed configuration
from 19,2Mhz source.

Change-Id: I22ea5200ab80713daaf40ae40f76073784f1fae9
Signed-off-by: Evgeniy Borisov <eborisov@codeaurora.org>