net/smc: unregister ib devices in reboot_event

In the reboot_event handler, unregister the ib devices and enable
the IB layer to release the devices before the reboot.

Fixes: a33a803c ("net/smc: guarantee removal of link groups in reboot")
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/smc/smc_core.c

@@ -1287,7 +1287,7 @@ static int smc_core_reboot_event(struct notifier_block *this,
 				 unsigned long event, void *ptr)
 {
 	smc_lgrs_shutdown();
-
+	smc_ib_unregister_client();
 	return 0;
 }