qla2xxx: Fix scsi_host leak on qlt_lport_register callback failure

This patch fixes a possible scsi_host reference leak in qlt_lport_register(),
when a non zero return from the passed (*callback) does not call drop the
local reference via scsi_host_put() before returning.

This currently does not effect existing tcm_qla2xxx code as the passed callback
will never fail, but fix this up regardless for future code.

Cc: Chad Dupuis <chad.dupuis@qlogic.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

drivers/scsi/qla2xxx/qla_target.c

@@ -4291,6 +4291,7 @@ int qlt_lport_register(struct qla_tgt_func_tmpl *qla_tgt_ops, u64 wwpn,
 		if (rc != 0) {
 			ha->tgt.tgt_ops = NULL;
 			ha->tgt.target_lport_ptr = NULL;
+			scsi_host_put(host);
 		}
 		mutex_unlock(&qla_tgt_mutex);
 		return rc;