mjpegdec: Properly set the context colorspace info

The JPEG spec requires it to be this.

Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
avfilter/vf_colormatrix: fix macro ()

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avfilter/vf_deshake: fix macro ()

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>