force option (-f) of umount.ecryptfs_private no longer works

According to the mount.ecryptfs_private.c source, the umount.ecryptfs_private program should accept a force option, -f, to forcibly unmount an encrypted home directory:

        /* Determine if mounting or unmounting by looking at the invocation */
        if (strstr(argv[0], "umount") == NULL) {
                mounting = 1;
        } else {
                mounting = 0;
                /* Determine if unmounting is forced */
                if (argv[1] != NULL && strncmp(argv[1], "-f", 2) == 0) {
                        force = 1;
                } else {
                        force = 0;
                }
        }

However, the alias support broke that option when it took over the argv[1] variable in r526. This results in an error when you try to force an unmount:

$ /sbin/umount.ecryptfs_private -f
Bad file
Error reading configuration file