[networking]device.h: Remove extern from function prototypes

There are a mix of function prototypes with and without extern
in the kernel sources.  Standardize on not using extern for
function prototypes.

Function prototypes don't need to be written with extern.
extern is assumed by the compiler.  Its use is as unnecessary as
using auto to declare automatic/local variables in a block.

Signed-off-by: Joe Perches <joe@perches.com>
diff --git a/include/linux/etherdevice.h b/include/linux/etherdevice.h
index d8b5124..fc4a9aa 100644
--- a/include/linux/etherdevice.h
+++ b/include/linux/etherdevice.h
@@ -28,27 +28,24 @@
 #include <asm/unaligned.h>
 
 #ifdef __KERNEL__
-extern __be16		eth_type_trans(struct sk_buff *skb, struct net_device *dev);
+__be16 eth_type_trans(struct sk_buff *skb, struct net_device *dev);
 extern const struct header_ops eth_header_ops;
 
-extern int eth_header(struct sk_buff *skb, struct net_device *dev,
-		      unsigned short type,
-		      const void *daddr, const void *saddr, unsigned len);
-extern int eth_rebuild_header(struct sk_buff *skb);
-extern int eth_header_parse(const struct sk_buff *skb, unsigned char *haddr);
-extern int eth_header_cache(const struct neighbour *neigh, struct hh_cache *hh, __be16 type);
-extern void eth_header_cache_update(struct hh_cache *hh,
-				    const struct net_device *dev,
-				    const unsigned char *haddr);
-extern int eth_prepare_mac_addr_change(struct net_device *dev, void *p);
-extern void eth_commit_mac_addr_change(struct net_device *dev, void *p);
-extern int eth_mac_addr(struct net_device *dev, void *p);
-extern int eth_change_mtu(struct net_device *dev, int new_mtu);
-extern int eth_validate_addr(struct net_device *dev);
+int eth_header(struct sk_buff *skb, struct net_device *dev, unsigned short type,
+	       const void *daddr, const void *saddr, unsigned len);
+int eth_rebuild_header(struct sk_buff *skb);
+int eth_header_parse(const struct sk_buff *skb, unsigned char *haddr);
+int eth_header_cache(const struct neighbour *neigh, struct hh_cache *hh,
+		     __be16 type);
+void eth_header_cache_update(struct hh_cache *hh, const struct net_device *dev,
+			     const unsigned char *haddr);
+int eth_prepare_mac_addr_change(struct net_device *dev, void *p);
+void eth_commit_mac_addr_change(struct net_device *dev, void *p);
+int eth_mac_addr(struct net_device *dev, void *p);
+int eth_change_mtu(struct net_device *dev, int new_mtu);
+int eth_validate_addr(struct net_device *dev);
 
-
-
-extern struct net_device *alloc_etherdev_mqs(int sizeof_priv, unsigned int txqs,
+struct net_device *alloc_etherdev_mqs(int sizeof_priv, unsigned int txqs,
 					    unsigned int rxqs);
 #define alloc_etherdev(sizeof_priv) alloc_etherdev_mq(sizeof_priv, 1)
 #define alloc_etherdev_mq(sizeof_priv, count) alloc_etherdev_mqs(sizeof_priv, count, count)