s4: libcli/finddcs_cldap: continue processing CLDAP until all addresses are used

s4: libcli/finddcs_cldap: continue processing CLDAP until all addresses are used

This is a subtle bug that causes CLDAP pings to fail if SRV records
discovered cannot be resolved or connection to them cannot be
established. The code that fires up CLDAP ping will silently cancel
the whole tevent request without going to the next server in the queue.

This may happen, for example, when connection to IPv6 addresses couldn't
be established, or when IPv4 address is not online or blocked by
firewall.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=11284

Signed-off-by: Alexander Bokovoy <ab@samba.org>
Reviewed-by: Stefan Metzmacher <metze@samba.org>
(cherry picked from commit eb029b32e95c9e7382488f3a1b033cdbe3237c1c)

Autobuild-User(v4-2-test): Karolin Seeger <kseeger@samba.org>
Autobuild-Date(v4-2-test): Thu May 21 20:06:21 CEST 2015 on sn-devel-104