media: mediatek: vcodec: decoder: Drop max_{width,height} from mtk_vcodec_ctx

This partially reverts commit b018be06 ("media: mediatek: vcodec:
Read max resolution from dec_capability").

After the previous patches:

  - media: mediatek: vcodec: decoder: Fix 4K frame size enumeration
  - media: mediatek: vcodec: decoder: Skip alignment for default resolution
  - media: mediatek: vcodec: decoder: Fix resolution clamping in TRY_FMT

the max_{width,height} fields in |struct mtk_vcodec_ctx| no longer have
any real users. Remove them.

Fixes: b018be06 ("media: mediatek: vcodec: Read max resolution from dec_capability")
Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
Tested-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>