vda: better frame allocation

Signed-off-by: Diego Biurrun <diego@biurrun.de>

libavcodec/vda_h264.c

@@ -144,7 +144,7 @@ static void vda_decoder_callback(void *vda_hw_ctx,
         vda_frame *new_frame;
         vda_frame *queue_walker;
 
-        if (!(new_frame = av_mallocz(sizeof(vda_frame))))
+        if (!(new_frame = av_mallocz(sizeof(*new_frame))))
             return;
         new_frame->next_frame = NULL;
         new_frame->cv_buffer  = CVPixelBufferRetain(image_buffer);