MAINTAINERS: adjust file entry in OMNIVISION OV7670 SENSOR DRIVER

Commit 59b24c00 ("media: dt-bindings: media: i2c: align filenames
format with standard") renames the files in
Documentation/devicetree/bindings/media/i2c/, but misses to adjust the file
entry in OMNIVISION OV7670 SENSOR DRIVER.

Adjust the file entry after this renaming.

Signed-off-by: Lukas Bulwahn <lukas.bulwahn@redhat.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: David Heidelberg <david@ixit.cz>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>