enic: fix incorrect MTU comparison in enic_change_mtu()

The comparison in enic_change_mtu() incorrectly used the current
netdev->mtu instead of the new new_mtu value when warning about
an MTU exceeding the port MTU. This could suppress valid warnings
or issue incorrect ones.

Fix the condition and log to properly reflect the new_mtu.

Fixes: ab123fe071c9 ("enic: handle mtu change for vf properly")
Signed-off-by: Alok Tiwari <[e-mail]>
Acked-by: John Daley <[e-mail]>
Reviewed-by: Simon Horman <[e-mail]>
Link: https://patch.msgid.link/[e-mail]
Signed-off-by: Jakub Kicinski <[e-mail]>

drivers/net/ethernet/cisco/enic/enic_main.c

···
 	if (enic_is_dynamic(enic) || enic_is_sriov_vf(enic))
 		return -EOPNOTSUPP;
 
-	if (netdev->mtu > enic->port_mtu)
+	if (new_mtu > enic->port_mtu)
 		netdev_warn(netdev,
 			    "interface MTU (%d) set higher than port MTU (%d)\n",
-			    netdev->mtu, enic->port_mtu);
+			    new_mtu, enic->port_mtu);
 
 	return _enic_change_mtu(netdev, new_mtu);
 }