NFC: Add support for SO_TIMESTAMP LLCP socket option

Set timestamp in sent and received sk_buffs. timestamp is then put in
msghdr structure in llcp_sock_recvmsg().

Signed-off-by: Thierry Escande <thierry.escande@linux.intel.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
diff --git a/net/nfc/llcp/llcp.c b/net/nfc/llcp/llcp.c
index ec43914..6c59714 100644
--- a/net/nfc/llcp/llcp.c
+++ b/net/nfc/llcp/llcp.c
@@ -668,6 +668,8 @@
 			if (ptype == LLCP_PDU_I)
 				copy_skb = skb_copy(skb, GFP_ATOMIC);
 
+			__net_timestamp(skb);
+
 			nfc_llcp_send_to_raw_sock(local, skb,
 						  NFC_LLCP_DIRECTION_TX);
 
@@ -1245,6 +1247,8 @@
 		print_hex_dump(KERN_DEBUG, "LLCP Rx: ", DUMP_PREFIX_OFFSET,
 			       16, 1, skb->data, skb->len, true);
 
+	__net_timestamp(skb);
+
 	nfc_llcp_send_to_raw_sock(local, skb, NFC_LLCP_DIRECTION_RX);
 
 	switch (ptype) {