efi_loader: efi_net: hwaddr_size = 6

The length of a MAC address is 6.
We have to set this length in the EFI_SIMPLE_NETWORK_MODE
structure of the EFI_SIMPLE_NETWORK_PROTOCOL.

Without this patch iPXE fails to initialize the network with
error message
SNP MAC(001e0633bcbf,0x0) has invalid hardware address length 0

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Alexander Graf <agraf@suse.de>

lib/efi_loader/efi_net.c

@@ -245,6 +245,7 @@ int efi_net_register(void)
 	netobj->net.mode = &netobj->net_mode;
 	netobj->net_mode.state = EFI_NETWORK_STARTED;
 	memcpy(netobj->net_mode.current_address.mac_addr, eth_get_ethaddr(), 6);
+	netobj->net_mode.hwaddr_size = ARP_HLEN;
 	netobj->net_mode.max_packet_size = PKTSIZE;
 
 	netobj->pxe.mode = &netobj->pxe_mode;