s4:kcc: Add a NULL check before qsort()
../source4/dsdb/kcc/kcc_topology.c: In function ‘kcctpl_get_all_bridgehead_dcs.constprop’:
../source4/dsdb/kcc/kcc_topology.c:1330:3: error: argument 1 null where non-null expected [-Werror=nonnull]
qsort(bridgeheads.data, bridgeheads.count,
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
BUG: https://bugzilla.samba.org/show_bug.cgi?id=13437
Signed-off-by: Andreas Schneider <asn@samba.org>
Reviewed-by: Guenther Deschner <gd@samba.org>
Autobuild-User(v4-7-test): Karolin Seeger <kseeger@samba.org>
Autobuild-Date(v4-7-test): Wed Jun 27 14:52:13 CEST 2018 on sn-devel-144