media: s5p_mfc_dec.c: convert g_crop to g_selection

The g_crop really implemented composition for the CAPTURE stream.

Replace g_crop by g_selection and set the V4L2_FL_QUIRK_INVERTED_CROP
flag since this is one of the old drivers that predates the selection
API. Those old drivers allowed g_crop when it really shouldn't have
since g_crop returns a compose rectangle instead of a crop rectangle.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Tested-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>