[PATCH] Make if_ether.h compile with CONFIG_SYSCTL=n

[PATCH] Make if_ether.h compile with CONFIG_SYSCTL=n

[Roland Dreier]

<linux/if_ether.h> tries to declare a sysctl table even if
CONFIG_SYSCTL is not defined, which breaks the build as below:

      CC      init/main.o
    In file included from /scratch/Ksrc/linux-git/include/linux/netdevice.h:29,
                     from /scratch/Ksrc/linux-git/include/net/sock.h:48,
                     from /scratch/Ksrc/linux-git/init/main.c:50:
    /scratch/Ksrc/linux-git/include/linux/if_ether.h:114: error: array type has incomplete element type

This patch wraps the declaration inside an #ifdef CONFIG_SYSCTL and
fixes my allnoconfig build.

Signed-off-by: Roland Dreier <rolandd@cisco.com>

diff --git a/include/linux/if_ether.h b/include/linux/if_ether.h
--- a/include/linux/if_ether.h
+++ b/include/linux/if_ether.h
@@ -104,6 +104,7 @@ struct ethhdr {
 } __attribute__((packed));
 
 #ifdef __KERNEL__
+#include <linux/config.h>
 #include <linux/skbuff.h>
 
 static inline struct ethhdr *eth_hdr(const struct sk_buff *skb)
@@ -111,7 +112,9 @@ static inline struct ethhdr *eth_hdr(con
 	return (struct ethhdr *)skb->mac.raw;
 }
 
+#ifdef CONFIG_SYSCTL
 extern struct ctl_table ether_table[];
 #endif
+#endif
 
 #endif	/* _LINUX_IF_ETHER_H */