networking: make skb_put & friends return void pointers

It seems like a historic accident that these return unsigned char *,
and in many places that means casts are required, more often than not.

Make these functions (skb_put, __skb_put and pskb_put) return void *
and remove all the casts across the tree, adding a (u8 *) cast only
where the unsigned char pointer was used directly, all done with the
following spatch:

    @@
    expression SKB, LEN;
    typedef u8;
    identifier fn = { skb_put, __skb_put };
    @@
    - *(fn(SKB, LEN))
    + *(u8 *)fn(SKB, LEN)

    @@
    expression E, SKB, LEN;
    identifier fn = { skb_put, __skb_put };
    type T;
    @@
    - E = ((T *)(fn(SKB, LEN)))
    + E = fn(SKB, LEN)

which actually doesn't cover pskb_put since there are only three
users overall.

A handful of stragglers were converted manually, notably a macro in
drivers/isdn/i4l/isdn_bsdcomp.c and, oddly enough, one of the many
instances in net/bluetooth/hci_sock.c. In the former file, I also
had to fix one whitespace problem spatch introduced.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/decnet/dn_nsp_out.c b/net/decnet/dn_nsp_out.c
index b8a5587..7e054b2 100644
--- a/net/decnet/dn_nsp_out.c
+++ b/net/decnet/dn_nsp_out.c
@@ -484,7 +484,7 @@ void dn_send_conn_ack (struct sock *sk)
 	if ((skb = dn_alloc_skb(sk, 3, sk->sk_allocation)) == NULL)
 		return;
 
-	msg = (struct nsp_conn_ack_msg *)skb_put(skb, 3);
+	msg = skb_put(skb, 3);
 	msg->msgflg = 0x24;
 	msg->dstaddr = scp->addrrem;
 
@@ -522,7 +522,7 @@ void dn_send_conn_conf(struct sock *sk, gfp_t gfp)
 	if ((skb = dn_alloc_skb(sk, 50 + len, gfp)) == NULL)
 		return;
 
-	msg = (struct nsp_conn_init_msg *)skb_put(skb, sizeof(*msg));
+	msg = skb_put(skb, sizeof(*msg));
 	msg->msgflg = 0x28;
 	msg->dstaddr = scp->addrrem;
 	msg->srcaddr = scp->addrloc;
@@ -530,7 +530,7 @@ void dn_send_conn_conf(struct sock *sk, gfp_t gfp)
 	msg->info = scp->info_loc;
 	msg->segsize = cpu_to_le16(scp->segsize_loc);
 
-	*skb_put(skb,1) = len;
+	*(u8 *)skb_put(skb, 1) = len;
 
 	if (len > 0)
 		skb_put_data(skb, scp->conndata_out.opt_data, len);
@@ -662,7 +662,7 @@ void dn_nsp_send_conninit(struct sock *sk, unsigned char msgflg)
 		return;
 
 	cb  = DN_SKB_CB(skb);
-	msg = (struct nsp_conn_init_msg *)skb_put(skb,sizeof(*msg));
+	msg = skb_put(skb, sizeof(*msg));
 
 	msg->msgflg	= msgflg;
 	msg->dstaddr	= 0x0000;		/* Remote Node will assign it*/
@@ -686,25 +686,25 @@ void dn_nsp_send_conninit(struct sock *sk, unsigned char msgflg)
 	if (scp->peer.sdn_flags & SDF_UICPROXY)
 		menuver |= DN_MENUVER_UIC;
 
-	*skb_put(skb, 1) = menuver;	/* Menu Version		*/
+	*(u8 *)skb_put(skb, 1) = menuver;	/* Menu Version		*/
 
 	aux = scp->accessdata.acc_userl;
-	*skb_put(skb, 1) = aux;
+	*(u8 *)skb_put(skb, 1) = aux;
 	if (aux > 0)
 		skb_put_data(skb, scp->accessdata.acc_user, aux);
 
 	aux = scp->accessdata.acc_passl;
-	*skb_put(skb, 1) = aux;
+	*(u8 *)skb_put(skb, 1) = aux;
 	if (aux > 0)
 		skb_put_data(skb, scp->accessdata.acc_pass, aux);
 
 	aux = scp->accessdata.acc_accl;
-	*skb_put(skb, 1) = aux;
+	*(u8 *)skb_put(skb, 1) = aux;
 	if (aux > 0)
 		skb_put_data(skb, scp->accessdata.acc_acc, aux);
 
 	aux = (__u8)le16_to_cpu(scp->conndata_out.opt_optl);
-	*skb_put(skb, 1) = aux;
+	*(u8 *)skb_put(skb, 1) = aux;
 	if (aux > 0)
 		skb_put_data(skb, scp->conndata_out.opt_data, aux);