media: imx274: rename IMX274_DEFAULT_MODE to IMX274_DEFAULT_BINNING

The "mode" has been renamed to "binning" in commit 39dd23dc
("media: imx274: add cropping support via SELECTION API"), but this
define has not been updated.

Signed-off-by: Luca Ceresoli <luca@lucaceresoli.net>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>