ibmvnic: save changed mac address to adapter->mac_addr

After mac address change request completes successfully, the new mac
address need to be saved to adapter->mac_addr as well as
netdev->dev_addr. Otherwise, adapter->mac_addr still holds old
data.

Fixes: 62740e97 ("net/ibmvnic: Update MAC address settings after adapter reset")
Signed-off-by: Lijun Pan <ljp@linux.ibm.com>
Link: https://lore.kernel.org/r/20201020223919.46106-1-ljp@linux.ibm.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>