[media] vcodec: mediatek: Add Mediatek V4L2 Video Encoder Driver

Add v4l2 layer encoder driver for MT8173

Signed-off-by: Tiffany Lin <tiffany.lin@mediatek.com>
[hans.verkuil@cisco.com: drop unnecessary ARM || ARM64 dependency]
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>