garp.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: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

include/net/garp.h

@@ -112,18 +112,17 @@ struct garp_port {
 	struct rcu_head			rcu;
 };
 
-extern int	garp_register_application(struct garp_application *app);
-extern void	garp_unregister_application(struct garp_application *app);
+int garp_register_application(struct garp_application *app);
+void garp_unregister_application(struct garp_application *app);
 
-extern int	garp_init_applicant(struct net_device *dev,
-				    struct garp_application *app);
-extern void	garp_uninit_applicant(struct net_device *dev,
+int garp_init_applicant(struct net_device *dev, struct garp_application *app);
+void garp_uninit_applicant(struct net_device *dev,
 			   struct garp_application *app);
 
-extern int	garp_request_join(const struct net_device *dev,
-				  const struct garp_application *app,
-				  const void *data, u8 len, u8 type);
-extern void	garp_request_leave(const struct net_device *dev,
+int garp_request_join(const struct net_device *dev,
+		      const struct garp_application *app, const void *data,
+		      u8 len, u8 type);
+void garp_request_leave(const struct net_device *dev,
 			const struct garp_application *app,
 			const void *data, u8 len, u8 type);