d3d11: Add support for GRAY and more YUV formats

By this commit, following formats will be newly supported by d3d11 elements

• Y444_{8, 12, 16}LE formats: Similar to other planar formats. Such Y444 variants are not supported by Direct3D11 natively, but we can simply map each plane by using R8 and/or R16 texture.
• P012_LE: It is not different from P016_LE, but defining P012 and P016 separately for more explicit signalling. Note that DXVA uses P016 texture for 12bits encoded bitstreams.
• GRAY: This format is required for some codecs (e.g., AV1) if monochrome is supported
• 4:2:0 planar 12bits (I420_12LE) and 4:2:2 planar 8, 10, 12bits formats (Y42B, I422_10LE, and I422_12LE)

added Windows label

assigned to @gstreamer-merge-bot

mentioned in commit seungha.yang/gst-plugins-bad@7c94b9c4

added 18 commits

• c20d7126...52a0c365 - 17 commits from branch gstreamer:master
• 7c94b9c4 - d3d11: Add support for GRAY and more YUV formats

Compare with previous version

merged

mentioned in issue #80 (closed)

changed milestone to %1.19.2