NFC: Add tx skb allocation routine

This is a factorization of the current rawsock tx skb allocation routine,
as it will be used by the LLCP code.
We also rename nfc_alloc_skb to nfc_alloc_recv_skb for consistency sake.

Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/nfc/rawsock.c b/net/nfc/rawsock.c
index 5e9b991..11ac0a1 100644
--- a/net/nfc/rawsock.c
+++ b/net/nfc/rawsock.c
@@ -208,13 +208,10 @@
 	if (sock->state != SS_CONNECTED)
 		return -ENOTCONN;
 
-	skb = sock_alloc_send_skb(sk, len + dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE,
-					msg->msg_flags & MSG_DONTWAIT, &rc);
-	if (!skb)
+	skb = nfc_alloc_send_skb(dev, sk, msg->msg_flags, len, &rc);
+	if (skb == NULL)
 		return rc;
 
-	skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
-
 	rc = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len);
 	if (rc < 0) {
 		kfree_skb(skb);