media: cedrus: h264: Fix check for presence of scaling matrix

If scaling matrix control is present, VPU should not use default matrix.
Fix that.

Fixes: b3a23db0

 ("media: cedrus: Use H264_SCALING_MATRIX only when required")
Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net>
Acked-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>