ui: Add missing 'static' attribute

There was already a forward declaration using 'static',
but the attribute was missing in the implementation.

This fixes a warning from the static code analysis (smatch).

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>

ui/console.c

@@ -1407,7 +1407,7 @@ void dpy_gfx_replace_surface(QemuConsole *con,
     qemu_free_displaysurface(old_surface);
 }
 
-void dpy_refresh(DisplayState *s)
+static void dpy_refresh(DisplayState *s)
 {
     DisplayChangeListener *dcl;