Ticket #48782 - Make sure that when LDAP_OPT_X_TLS_NEWCTX is set, the value is set to zero.
Description: The attached patch is for the optval issue described above.
Optval is explicitly set to zero, rather than using whatever arbitrary
value is present in optval from the earlier ldap_set_option call.
https://fedorahosted.org/389/ticket/48782
Reviewed by nhosoi@redhat.com.