Get rid of several unneeded includes (if.h, if_var.h, if_mib.h).

sbin/atm/atmconfig/natm.c

@@ -32,9 +32,6 @@ __FBSDID("$FreeBSD$");
 #include <sys/types.h>
 #include <sys/socket.h>
 #include <sys/sysctl.h>
-#include <net/if.h>
-#include <net/if_var.h>
-#include <net/if_mib.h>
 #include <net/if_atm.h>
 #include <net/if_dl.h>
 #include <net/route.h>