ehea: restore multicast and rx_errors fields

Commit 239c562c

 (ehea: Add 64bit statistics) added a regression,
since we no longer report multicast & rx_errors fields, taken from
port->stats structure. These fields are updated in ehea_update_stats()
every second.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Anton Blanchard <anton@samba.org>
Cc: Thadeu Lima de Souza Cascardo <cascardo@linux.vnet.ibm.com>
Acked-by: Thadeu Lima de Souza Cascardo <cascardo@linux.vnet.ibm.com>
Tested-by: Thadeu Lima de Souza Cascardo <cascardo@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>