[media] vcodec: mediatek: Add V4L2_CAP_TIMEPERFRAME capability setting

This patch setting V4L2_CAP_TIMEPERFRAME capability in
vidioc_venc_s/g_parm functions

Signed-off-by: Tiffany Lin <tiffany.lin@mediatek.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>