net: l2tp: Standardize logging styles

Use more current logging styles.

Add pr_fmt to prefix output appropriately.
Convert printks to pr_<level>.
Convert PRINTK macros to new l2tp_<level> macros.
Neaten some <foo>_refcount debugging macros.
Use print_hex_dump_bytes instead of hand-coded loops.
Coalesce formats and align arguments.

Some KERN_DEBUG output is not now emitted unless
dynamic_debugging is enabled.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/l2tp/l2tp_eth.c b/net/l2tp/l2tp_eth.c
index 63fe5f3..443591d 100644
--- a/net/l2tp/l2tp_eth.c
+++ b/net/l2tp/l2tp_eth.c
@@ -9,6 +9,8 @@
  *	2 of the License, or (at your option) any later version.
  */
 
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
 #include <linux/module.h>
 #include <linux/skbuff.h>
 #include <linux/socket.h>
@@ -115,21 +117,14 @@
 
 	if (session->debug & L2TP_MSG_DATA) {
 		unsigned int length;
-		int offset;
 		u8 *ptr = skb->data;
 
 		length = min(32u, skb->len);
 		if (!pskb_may_pull(skb, length))
 			goto error;
 
-		printk(KERN_DEBUG "%s: eth recv: ", session->name);
-
-		offset = 0;
-		do {
-			printk(" %02X", ptr[offset]);
-		} while (++offset < length);
-
-		printk("\n");
+		pr_debug("%s: eth recv\n", session->name);
+		print_hex_dump_bytes("", DUMP_PREFIX_OFFSET, ptr, length);
 	}
 
 	if (!pskb_may_pull(skb, sizeof(ETH_HLEN)))
@@ -308,7 +303,7 @@
 	if (err)
 		goto out_unreg;
 
-	printk(KERN_INFO "L2TP ethernet pseudowire support (L2TPv3)\n");
+	pr_info("L2TP ethernet pseudowire support (L2TPv3)\n");
 
 	return 0;