Fix strict prototype warnings

src/fe-gtk/menu.c

@@ -375,7 +375,7 @@ menu_quick_sub (char *name, GtkWidget *menu, GtkWidget **sub_item_ret, int flags
 }
 
 static GtkWidget *
-menu_quick_endsub ()
+menu_quick_endsub (void)
 {
 	/* Just delete the first element in the linked list pointed to by first */
 	if (submenu_list)
@@ -1259,7 +1259,7 @@ menu_quit (GtkWidget * wid, gpointer none)
 }
 
 static void
-menu_search ()
+menu_search (void)
 {
 	mg_search_toggle (current_sess);
 }