Always set submenu to False with compizboxmenu

Since the menu will always show up in a submenu with compizboxmenu,
there's no need to have a nested submenu in there.

src/xdgmenumaker

@@ -189,6 +189,7 @@ def main(argv):
     elif desktop == "jwm":
         jwmmenu()
     elif desktop == "compizboxmenu":
+        submenu = False
         compizboxmenu()
     else:
         usage()