media: staging: media: imx: imx7-media-csi: Drop unneeded imx7_csi_pixfmt fields

The imx7_csi_pixfmt cycles field is never used nor set, the bayer field
is never used, and the planar field is never set. Drop them.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Rui Miguel Silva <rmfrfs@gmail.com>
Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>