Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Add const qualifier to the dst parameter of the ifnet if_output method.

/* -> /*- for license, minor formatting changes

White space cleanup for netinet before branch:

- Trailing tab/space cleanup
- Remove spurious spaces between or before tabs

This change avoids touching files that Andre likely has in his working
set for PFIL hooks changes for IPFW/DUMMYNET.

Approved by: re (scottl)
Submitted by: Xin LI <delphij@frontfree.net>

Remove __P.

Pull post-4.4BSD change to sys/net/route.c from BSD/OS 4.2.

Have sys/net/route.c:rtrequest1(), which takes ``rt_addrinfo *''
as the argument. Pass rt_addrinfo all the way down to rtrequest1
and ifa->ifa_rtrequest. 3rd argument of ifa->ifa_rtrequest is now
``rt_addrinfo *'' instead of ``sockaddr *'' (almost noone is
using it anyways).

Benefit: the following command now works. Previously we needed
two route(8) invocations, "add" then "change".
# route add -inet6 default ::1 -ifp gif0

Remove unsafe typecast in rtrequest(), from ``rtentry *'' to
``sockaddr *''. It was introduced by 4.3BSD-Reno and never
corrected.

Obtained from: BSD/OS, NetBSD
MFC after: 1 month
PR: kern/28360

Add $FreeBSD$

Forward declare some structs so that this file is more self-sufficient.

This commit was generated by cvs2svn to compensate for changes in r25603,
which included commits to RCS files with non-trunk default branches.

import Chuck Cranor's ATM driver