media: dt-bindings: media: i2c: Fix i2c address for OV5645 camera sensor

The i2c address for the Omnivision OV5645 camera sensor is 0x3c. It is
incorrectly mentioned as 0x78 in binding. Hence fix that.

Fixes: 09c716af [media] media: i2c/ov5645: add the device tree binding document

Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>