clean up redundant, commented-out and misplaced includes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/networking/interface.c b/networking/interface.c
index 0d5a0f9..b59a61d 100644
--- a/networking/interface.c
+++ b/networking/interface.c
@@ -33,14 +33,18 @@
 
 #include <net/if.h>
 #include <net/if_arp.h>
+#if (defined(__GLIBC__) && __GLIBC__ >= 2 && __GLIBC_MINOR__ >= 1) || defined(_NEWLIB_VERSION)
+# include <net/ethernet.h>
+#else
+# include <linux/if_ether.h>
+#endif
 #include "libbb.h"
 #include "inet_common.h"
 
-
 #if ENABLE_FEATURE_HWIB
 /* #include <linux/if_infiniband.h> */
-#undef INFINIBAND_ALEN
-#define INFINIBAND_ALEN 20
+# undef INFINIBAND_ALEN
+# define INFINIBAND_ALEN 20
 #endif
 
 #if ENABLE_FEATURE_IPV6
@@ -53,39 +57,35 @@
 #define _PATH_PROCNET_IFINET6           "/proc/net/if_inet6"
 
 #ifdef HAVE_AFINET6
-
-#ifndef _LINUX_IN6_H
+# ifndef _LINUX_IN6_H
 /*
- *    This is in linux/include/net/ipv6.h.
+ * This is from linux/include/net/ipv6.h
  */
-
 struct in6_ifreq {
 	struct in6_addr ifr6_addr;
 	uint32_t ifr6_prefixlen;
 	unsigned int ifr6_ifindex;
 };
-
-#endif
-
+# endif
 #endif /* HAVE_AFINET6 */
 
 /* Defines for glibc2.0 users. */
 #ifndef SIOCSIFTXQLEN
-#define SIOCSIFTXQLEN      0x8943
-#define SIOCGIFTXQLEN      0x8942
+# define SIOCSIFTXQLEN      0x8943
+# define SIOCGIFTXQLEN      0x8942
 #endif
 
 /* ifr_qlen is ifru_ivalue, but it isn't present in 2.0 kernel headers */
 #ifndef ifr_qlen
-#define ifr_qlen        ifr_ifru.ifru_mtu
+# define ifr_qlen        ifr_ifru.ifru_mtu
 #endif
 
 #ifndef HAVE_TXQUEUELEN
-#define HAVE_TXQUEUELEN 1
+# define HAVE_TXQUEUELEN 1
 #endif
 
 #ifndef IFF_DYNAMIC
-#define IFF_DYNAMIC     0x8000	/* dialup device with changing addresses */
+# define IFF_DYNAMIC     0x8000 /* dialup device with changing addresses */
 #endif
 
 /* Display an Internet socket address. */
@@ -711,14 +711,6 @@
 	.type =		ARPHRD_LOOPBACK
 };
 
-#include <net/if_arp.h>
-
-#if (defined(__GLIBC__) && __GLIBC__ >= 2 && __GLIBC_MINOR__ >= 1) || defined(_NEWLIB_VERSION)
-#include <net/ethernet.h>
-#else
-#include <linux/if_ether.h>
-#endif
-
 /* Display an Ethernet address in readable format. */
 static char* FAST_FUNC ether_print(unsigned char *ptr)
 {
@@ -794,8 +786,6 @@
 	return 0;
 }
 
-#include <net/if_arp.h>
-
 static const struct hwtype ppp_hwtype = {
 	.name =		"ppp",
 	.title =	"Point-to-Point Protocol",
@@ -993,7 +983,6 @@
 #define ife_print6(a) ((void)0)
 #endif
 
-
 static void ife_print(struct interface *ptr)
 {
 	const struct aftype *ap;
@@ -1277,7 +1266,6 @@
 }
 #endif
 
-
 int FAST_FUNC display_interfaces(char *ifname)
 {
 	int status;