avfilter/vf_spp: add gbrp support

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavfilter/vf_spp.c

@@ -322,6 +322,7 @@ static int query_formats(AVFilterContext *ctx)
         AV_PIX_FMT_YUV444P10,  AV_PIX_FMT_YUV422P10,
         AV_PIX_FMT_YUV420P10,
         AV_PIX_FMT_GRAY8,
+        AV_PIX_FMT_GBRP,
         AV_PIX_FMT_NONE
     };
     ff_set_common_formats(ctx, ff_make_format_list(pix_fmts));