[krbdev.mit.edu #4136] kadmin_unlock() calls kadm5_lock() instead of kadm5_unlock()

[Public Submitter via RT]

from krb 1.5 src/kadmin/cli/kadmin.c:597

kadmin_unlock() calls kadm5_lock() when it should be calling
kadm5_unlock(), this in effect makes the "unlock" subcommand of kadmin
useless.

See attached diff for suggested fix.