interface: add capabilities flags

Type: improvement

This patch adds flags to represent the modern NICs capabilities.

Change-Id: I96d38d9ab7eac55974d72795cd100d8337168e1e
Signed-off-by: Mohsin Kazmi <sykazmi@cisco.com>
diff --git a/src/vnet/interface_output.c b/src/vnet/interface_output.c
index d244765..c46868e 100644
--- a/src/vnet/interface_output.c
+++ b/src/vnet/interface_output.c
@@ -491,7 +491,7 @@
   vnet_interface_pcap_tx_trace (vm, node, frame,
 				0 /* sw_if_index_from_buffer */ );
 
-  if (hi->flags & VNET_HW_INTERFACE_FLAG_SUPPORTS_TX_L4_CKSUM_OFFLOAD)
+  if (hi->caps & VNET_HW_INTERFACE_CAP_SUPPORTS_TX_CKSUM)
     return vnet_interface_output_node_inline (vm, node, frame, vnm, hi,
 					      /* do_tx_offloads */ 0);
   else