aux/trace: add missing return value to trace output

trace_screen_resource_bind_backing() was missing printing of
the boolean return value. Add it.

Reviewed-By: Mike Blumenkrantz <michael.blumenkrantz@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/10900>

src/gallium/auxiliary/driver_trace/tr_screen.c

@@ -475,6 +475,8 @@ trace_screen_resource_bind_backing(struct pipe_screen *_screen,
 
    result = screen->resource_bind_backing(screen, resource, pmem, offset);
 
+   trace_dump_ret(bool, result);
+
    trace_dump_call_end();
 
    return result;