net: Remove casts to same type

Adding casts of objects to the same type is unnecessary
and confusing for a human reader.

For example, this cast:

	int y;
	int *p = (int *)&y;

I used the coccinelle script below to find and remove these
unnecessary casts.  I manually removed the conversions this
script produces of casts with __force and __user.

@@
type T;
T *p;
@@

-	(T *)p
+	p

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/l2tp/l2tp_ppp.c b/net/l2tp/l2tp_ppp.c
index 8ef6b94..286366e 100644
--- a/net/l2tp/l2tp_ppp.c
+++ b/net/l2tp/l2tp_ppp.c
@@ -1522,8 +1522,8 @@
  * handler, according to whether the PPPoX socket is a for a regular session
  * or the special tunnel type.
  */
-static int pppol2tp_getsockopt(struct socket *sock, int level,
-			       int optname, char __user *optval, int __user *optlen)
+static int pppol2tp_getsockopt(struct socket *sock, int level, int optname,
+			       char __user *optval, int __user *optlen)
 {
 	struct sock *sk = sock->sk;
 	struct l2tp_session *session;
@@ -1535,7 +1535,7 @@
 	if (level != SOL_PPPOL2TP)
 		return udp_prot.getsockopt(sk, level, optname, optval, optlen);
 
-	if (get_user(len, (int __user *) optlen))
+	if (get_user(len, optlen))
 		return -EFAULT;
 
 	len = min_t(unsigned int, len, sizeof(int));
@@ -1568,7 +1568,7 @@
 		err = pppol2tp_session_getsockopt(sk, session, optname, &val);
 
 	err = -EFAULT;
-	if (put_user(len, (int __user *) optlen))
+	if (put_user(len, optlen))
 		goto end_put_sess;
 
 	if (copy_to_user((void __user *) optval, &val, len))