ixgbevf: add check for CHECKSUM_PARTIAL when doing TSO

This patch adds check for CHECKSUM_PARTIAL to avoid the skb_is_gso check
in ixgbevf_tso(). It should reduce overhead for workloads that are not using
TSO or checksum offloads. It is the same as in ixgbe.

Signed-off-by: Emil Tantilov <emil.s.tantilov@intel.com>
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c

@@ -2777,6 +2777,9 @@ static int ixgbevf_tso(struct ixgbevf_ring *tx_ring,
 	u32 vlan_macip_lens, type_tucmd;
 	u32 mss_l4len_idx, l4len;
 
+	if (skb->ip_summed != CHECKSUM_PARTIAL)
+		return 0;
+
 	if (!skb_is_gso(skb))
 		return 0;