Oops, we shoudn't let DOS_FILE and MAX_FILE be set at the same time

git-svn-id: svn://svn.savannah.gnu.org/nano/trunk/nano@784 35c25a1d-7b9e-4130-9fde-d3aeb78583b8

nano.c

@@ -2359,7 +2359,12 @@ void do_toggle(int which)
 	edit_refresh();
 	display_main_list();
 	break;
-
+    case TOGGLE_DOS_KEY:
+	UNSET(MAC_FILE);
+	break;
+    case TOGGLE_MAC_KEY:
+	UNSET(DOS_FILE);
+	break;
     }
 
     if (!ISSET(toggles[which].flag)) {