d3d11h265dec: Add support for interlaced stream

    d3d11h265dec: Add support for interlaced stream

    Note that we have no D3D11 deinterlace element yet.

    If downstream is not support format:Interlaced caps feature including all
    D3D11 the other elements, aspect-ratio will be adjusted as an
    alternative approach.

    codecs: h265decoder: Add support for interlaced stream

    * Invoke GstH265DecoderClass::new_sequence() method per interlaced
      stream status update so that subclass can update caps.
    * Parse picture timing SEI and set buffer flags on GstH265Picture
      object. Subclass can refer to it like that of our h264decoder
      implementation.
    * Remove pointless GstH265PictureField enum

    vah265dec: Don't need to pass picture structure to VA

    This code came from gstvaapidecoder_h265 implementation
    but picture structure is always GST_VAAPI_PICTURE_STRUCTURE_FRAME.
    Moreover, in theory, VA doesn't need to know picture structure for
    decoding HEVC stream.

    nvh265sldec: Remove pointless field picture parameter setup

    HEVC has no decoding flow for interlaced, field picture referencing.

sys/va/gstvah265dec.c

@@ -193,20 +193,6 @@ _fill_vaapi_pic (GstH265Decoder * decoder, VAPictureHEVC * va_picture,
     va_picture->flags |= VA_PICTURE_HEVC_LONG_TERM_REFERENCE;
 
   va_picture->flags |= _find_frame_rps_type (decoder, picture);
-
-  switch (picture->field) {
-    case GST_H265_PICTURE_FIELD_FRAME:
-      break;
-    case GST_H265_PICTURE_FILED_TOP_FIELD:
-      va_picture->flags |= VA_PICTURE_HEVC_FIELD_PIC;
-      break;
-    case GST_H265_PICTURE_FIELD_BOTTOM_FIELD:
-      va_picture->flags |= VA_PICTURE_HEVC_FIELD_PIC;
-      va_picture->flags |= VA_PICTURE_HEVC_BOTTOM_FIELD;
-      break;
-    default:
-      break;
-  }
 }
 
 static guint8