Allow timers to exist but be inactive.
This will be used in a future commit.

White space police.

branches: 1.8.14;
Use clock_gettime(2) instead of gettimeofday(2) so we can use a monotonic
clock rather than the wall clock.
Use timespec rather than timeval structs to make this transition easier.
Kill custom timeval comparison functions in favor of timespeccmp(3).

Add RDNSS and DNSSL support, RFC6106.
Replace custom lists with TAILQ lists.
Clean up plently of signed vs unsigned warnings and set WARNS=4.

Adapted from FreeBSD.

branches: 1.6.42;
NDP-related improvements:
RFC4191
- supports host-side router-preference

RFC3542
- if DAD fails on a interface, disables IPv6 operation on the
interface
- don't advertise MLD report before DAD finishes

Others
- fixes integer overflow for valid and preferred lifetimes
- improves timer granularity for MLD, using callout-timer.
- reflects rtadvd's IPv6 host variable information into kernel
(router only)
- adds a sysctl option to enable/disable pMTUd for multicast
packets
- performs NUD on PPP/GRE interface by default
- Redirect works regardless of ip6_accept_rtadv
- removes RFC1885-related code

From the KAME project via SUZUKI Shinsuke.
Reviewed by core.

KNF. a memory leak fix. sync w/kame

sync with sys/netinet/icmp6.h change (no bitfield for router renumber).
more logging. improve error handling/garbage collection. sync with kame.

branches: 1.3.4;
sync with latest kame.
- decrease warning level on missing rtadvd.conf (actually, the file
can be omitted)
- strict prototype
- gather stats better, emit stats on SIGUSR1 to /var/run

fix for 64bit arch, where sizeof(size_t) != sizeof(int).
add NetBSD RCS ID.

rtadvd: advertise IPv6 prefix info via router advertisement.
(to be run on routers)