media: imx-jpeg: Correct the pixel format of rgb

The hardware is capable of encoding/decoding RGB and ARGB formats
in whatever order the color components are,
but the resulting jpegs look good
if we start with raw data in BGR/ABGR order,
so we will further only support V4L2_PIX_FMT_BGR24 and V4L2_PIX_FMT_ABGR32.

Signed-off-by: Ming Qian <ming.qian@nxp.com>
Reviewed-by: Mirela Rabulea <mirela.rabulea@nxp.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>