switch_root: stop at first non-option. Closes bug 1425.

util-linux/switch_root.c

@@ -73,8 +73,8 @@ int switch_root_main(int argc, char **argv)
 
 	// Parse args (-c console)
 
-	opt_complementary = "-2";
-	getopt32(argv, "c:", &console);
+	opt_complementary = "-2"; // minimum 2 params
+	getopt32(argv, "+c:", &console); // '+': stop parsing at first non-option
 	argv += optind;
 
 	// Change to new root directory and verify it's a different fs.