fm10k: fix VLAN in Rx mbuf

fm10k: fix VLAN in Rx mbuf

vlan_tci should be copied from RX descriptor to mbuf,
and flag PKT_RX_VLAN_PKT should be set for every RX packet,
this patch fixes this issue.
Packets in fm10k device always carry at least one VLAN tag.
For those packets coming in without VLAN tag,
the port default VLAN tag will be used.
So in fm10k, always PKT_RX_VLAN_PKT flag is set and vlan_tci
is valid for each RX packet's mbuf.

Signed-off-by: Shaopeng He <shaopeng.he@intel.com>
Acked-by: Stephen Hemminger <stephen@networkplumber.org>