Make kdb5_util dump work with LDAP again

The LDAP module doesn't support locking.  There's code to ignore this
in load but not in dump.  dump used to only lock for iprop dumps, but
now locks all the time after e65a16d898f3a686525e83661f4fd86c76e27bbf
(#7384), causing it to fail with LDAP.

https://github.com/krb5/krb5/commit/2df36dd4a52c2b08fbacf1648dc76e8e313ce1b5
Author: Greg Hudson <ghudson@mit.edu>
Commit: 2df36dd4a52c2b08fbacf1648dc76e8e313ce1b5
Branch: master
 src/kadmin/dbutil/dump.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)