avcodec/dxva2_vc1: add missing frame_params callback to vc1_d3d11va2 hwaccel

Fixes ticket #7096
Reviewed-by: wm4 <nfxjfg@googlemail.com>
Signed-off-by: James Almer <jamrial@gmail.com>

libavcodec/dxva2_vc1.c

@@ -473,6 +473,7 @@ const AVHWAccel ff_vc1_d3d11va2_hwaccel = {
     .start_frame    = dxva2_vc1_start_frame,
     .decode_slice   = dxva2_vc1_decode_slice,
     .end_frame      = dxva2_vc1_end_frame,
+    .frame_params   = ff_dxva2_common_frame_params,
     .frame_priv_data_size = sizeof(struct dxva2_picture_context),
     .priv_data_size = sizeof(FFDXVASharedContext),
 };