'RELENG_4_1_0_RELEASE'.

This commit was manufactured to restore the state of the 4.1-RELEASE image.
Releases prior to 5.3-RELEASE are omitting the secure/ and crypto/ subdirs.

This is fix to usr.sbin/trpt and tcp_debug.[ch]
I think of putting this after 4.0 but,,,

 -There was bug that when INET6 is defined,
  IPv4 socket is not traced by trpt.

 -I received request from a person who distribute a program
  which use tcp_debug interface and print performance statistics,
  that
    -leave comptibility with old program as much as possible
    -use same interface with other OSes

  So, I talked with itojun, and synced API with netbsd IPv6 extension.

makeworld check, kernel build check(includes GENERIC) is done.

But if there happen to any problem, please let me know and
I soon backout this change.

also a small patch to sys/nfs/nfs_socket.c, as max_hdr size change.

Reviewed by: freebsd-arch, cvs-committers
Obtained from: KAME project

This will not make any of object files that LINT create change; there
might be differences with INET disabled, but hardly anything compiled
before without INET anyway.  Now the 'obvious' things will give a
proper error if compiled without inet - ipx_ip, ipfw, tcp_debug.  The
only thing that _should_ work (but can't be made to compile reasonably
easily) is sppp :-(

This commit move struct arpcom from <netinet/if_ether.h> to
<net/if_arp.h>.

ready for it yet.