Revert r13542: Spatial direct mode probably also works with PAFF.

Originally committed as revision 14332 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/h264.c

@@ -4117,8 +4117,6 @@ static int decode_slice_header(H264Context *h, H264Context *h0){
     if(h->slice_type_nos != FF_I_TYPE){
         if(h->slice_type_nos == FF_B_TYPE){
             h->direct_spatial_mv_pred= get_bits1(&s->gb);
-            if(FIELD_PICTURE && h->direct_spatial_mv_pred)
-                av_log(h->s.avctx, AV_LOG_ERROR, "PAFF + spatial direct mode is not implemented\n");
         }
         num_ref_idx_active_override_flag= get_bits1(&s->gb);