devices: fix af_packet GSO check
devices: fix af_packet GSO check

Type: fix

This fixes the GSO size calculation in af_packet
which didn't include the ethernet size.
This is not ideal, as we default to the host
side mtu to check whether a packet is GSO or not
and to set the GSO size. But there doesn't seem
to be more info passed with the packets.

Change-Id: I9769e1dd21d5989b4cf67295352b5535454f88d1
Signed-off-by: Nathan Skrzypczak <0fa918c439baf617eab84c5ae2a48ee9db643966@gmail.com>

chrisy/vpp,FDio/vpp,FDio/vpp,FDio/vpp,chrisy/vpp,chrisy/vpp,FDio/vpp,chrisy/vpp,FDio/vpp,FDio/vpp,FDio/vpp,chrisy/vpp,chrisy/vpp,FDio/vpp,chrisy/vpp,chrisy/vpp