[media] coda: drop custom list of pixel format descriptions

Since commit ba300204 ("[media] v4l2-ioctl: fill in the description
for VIDIOC_ENUM_FMT"), all pixel formats are assigned their description
in a central place. We can now drop the custom list.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>