Remove duplicated format mapping code Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/5706>
... and remove duplicated code Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/3310>
Recent Intel GPU supports 12bits VP9 decoding but only VP9 profile2 with 10bits is defined by DXVA spec. Thus, we need this vendor specific decoder element Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/3290>