net/ibmvnic: Fix RTNL deadlock during device reset

Commit a5681e20 ("net/ibmnvic: Fix deadlock problem
in reset") made the change to hold the RTNL lock during
driver reset but still calls netdev_notify_peers, which
results in a deadlock. Instead, use call_netdevice_notifiers,
which is functionally the same except that it does not
take the RTNL lock again.

Fixes: a5681e20 ("net/ibmnvic: Fix deadlock problem in reset")
Signed-off-by: Thomas Falcon <tlfalcon@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>