mmal/deinterlace: Clear data from buffer header before release

The data attached to the output port headers is not owned by the deinterlace
filter but by the vout and only temporarily attached to the codecs buffers. To
avoid refcount issues within the mmal core clear the data field before
releasing the buffers.
Signed-off-by: Julian Scheel <julian@jusst.de>
Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>

modules/hw/mmal/deinterlace.c

@@ -522,8 +522,10 @@ static void input_port_cb(MMAL_PORT_T *port, MMAL_BUFFER_HEADER_T *buffer)
     filter_t *filter = (filter_t *)port->userdata;
     filter_sys_t *sys = filter->p_sys;
 
-    buffer->user_data = NULL;
     vlc_mutex_lock(&sys->buffer_cond_mutex);
+    buffer->user_data = NULL;
+    buffer->alloc_size = 0;
+    buffer->data = NULL;
     mmal_buffer_header_release(buffer);
     if (picture)
         picture_Release(picture);
@@ -547,6 +549,10 @@ static void output_port_cb(MMAL_PORT_T *port, MMAL_BUFFER_HEADER_T *buffer)
             picture = (picture_t *)buffer->user_data;
             picture_Release(picture);
             buffer->user_data = NULL;
+            buffer->alloc_size = 0;
+            buffer->data = NULL;
+            mmal_buffer_header_reset(buffer);
+            mmal_buffer_header_release(buffer);
         }
 
         atomic_fetch_sub(&sys->output_in_transit, 1);