ui/sdl2: Support shared surface for more pixman formats

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
diff --git a/include/ui/sdl2.h b/include/ui/sdl2.h
index f56c596..51fff2e 100644
--- a/include/ui/sdl2.h
+++ b/include/ui/sdl2.h
@@ -28,5 +28,7 @@
                     DisplaySurface *new_surface);
 void sdl2_2d_refresh(DisplayChangeListener *dcl);
 void sdl2_2d_redraw(struct sdl2_console *scon);
+bool sdl2_2d_check_format(DisplayChangeListener *dcl,
+                          pixman_format_code_t format);
 
 #endif /* SDL2_H */