- Fix already defined command warnings for minimize

- Fix recursive CL_Shutdown warning and "command already defined" warnings when quitting while playing on a server that changed the gamedir.

code/null/null_client.c

@@ -25,7 +25,7 @@ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 
 cvar_t *cl_shownet;
 
-void CL_Shutdown(char *finalmsg, qboolean disconnect)
+void CL_Shutdown(char *finalmsg, qboolean disconnect, qboolean quit)
 {
 }