net/enic: fix header sizes when copying flow patterns

net/enic: fix header sizes when copying flow patterns

Several functions use sizeof(struct rte_flow_item_eth) and
sizeof(struct rte_flow_item_ipv6) when copying headers. These sizes
used to coincide with the sizes of rte_ether_hdr and
rte_ipv6_hdr. But, with recently added fields, rte_flow_item_eth and
rte_flow_item_ipv6 have grown in size. Use sizeof(rte_ether_hdr) and
sizeof(rte_ipv6_hdr) instead.

Coverity issue: 363572, 363573
Fixes: ea7768b5bba8 ("net/enic: add flow implementation based on Flow Manager API")
Cc: stable@dpdk.org
Signed-off-by: Hyong Youb Kim <hyonkim@cisco.com>
Reviewed-by: John Daley <johndale@cisco.com>