ieee802154: 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>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ieee802154/6lowpan_rtnl.c b/net/ieee802154/6lowpan_rtnl.c
index 1bbab89..48a8f52 100644
--- a/net/ieee802154/6lowpan_rtnl.c
+++ b/net/ieee802154/6lowpan_rtnl.c
@@ -613,7 +613,7 @@
 };
 
 static struct packet_type lowpan_packet_type = {
-	.type = __constant_htons(ETH_P_IEEE802154),
+	.type = htons(ETH_P_IEEE802154),
 	.func = lowpan_rcv,
 };