net/i40e: implement new Rx checksum flag
net/i40e: implement new Rx checksum flag

Add CKSUM_GOOD flag to distinguish a good checksum from an unknown one.

Signed-off-by: Xiao Wang <28aecb4e45c1566b6185c24680691da84bd4fcf8@intel.com>
Acked-by: Jing Chen <2b730c2e01419ef3cbe586e212d13b674b74d017@intel.com>

john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk