qsv: Default PicStruct to progressive

The PicStruct is required by MediaSDK, so give a default value.
hwupload does not work without this.

Signed-off-by: Ruiling Song <ruiling.song@intel.com>
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>

libavutil/hwcontext_qsv.c

@@ -313,6 +313,7 @@ static int qsv_init_surface(AVHWFramesContext *ctx, mfxFrameSurface1 *surf)
     surf->Info.CropH          = ctx->height;
     surf->Info.FrameRateExtN  = 25;
     surf->Info.FrameRateExtD  = 1;
+    surf->Info.PicStruct      = MFX_PICSTRUCT_PROGRESSIVE;
 
     return 0;
 }