ixgbevf: Convert uses of __constant_<foo> to <foo>

The use of __constant_<foo> has been unnecessary for quite awhile now.

Make these uses consistent with the rest of the kernel.
Signed-off-by: Joe Perches <joe@perches.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

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

@@ -2857,12 +2857,12 @@ static void ixgbevf_tx_csum(struct ixgbevf_ring *tx_ring,
 	if (skb->ip_summed == CHECKSUM_PARTIAL) {
 		u8 l4_hdr = 0;
 		switch (skb->protocol) {
-		case __constant_htons(ETH_P_IP):
+		case htons(ETH_P_IP):
 			vlan_macip_lens |= skb_network_header_len(skb);
 			type_tucmd |= IXGBE_ADVTXD_TUCMD_IPV4;
 			l4_hdr = ip_hdr(skb)->protocol;
 			break;
-		case __constant_htons(ETH_P_IPV6):
+		case htons(ETH_P_IPV6):
 			vlan_macip_lens |= skb_network_header_len(skb);
 			l4_hdr = ipv6_hdr(skb)->nexthdr;
 			break;