media: mediatek: vcodec: Force capture queue format to MM21

While the decoder can produce frames in both MM21 and MT21C formats, only
MM21 is currently supported by userspace tools (like gstreamer and libyuv).
In order to ensure userspace keeps working after the SCP firmware is
updated to support both MM21 and MT21C formats, force the MM21 format for
the capture queue.

This is meant as a stopgap solution while dynamic format switching between
MM21 and MT21C isn't implemented in the driver.

Fixes: 7501edef ("media: mediatek: vcodec: Different codec using different capture format")
Signed-off-by: Yunfei Dong <yunfei.dong@mediatek.com>
Reviewed-by: Nicolas F. R. A. Prado <nfraprado@collabora.com>
Tested-by: Nicolas F. R. A. Prado <nfraprado@collabora.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>