netinet6: Add sysctl flag CTLFLAG_TUN to loader tunables
The following sysctl variables are actually loader tunables. Add sysctl
flag CTLFLAG_TUN to them so that sysctl -T will report them correctly.
- net.inet6.ip6.auto_linklocal
- net.inet6.ip6.accept_rtadv
- net.inet6.ip6.no_radr
No functional change intended.
Reviewed by: glebius
MFC after: 3 days
Differential Revision: https://reviews.freebsd.org/D41928
(cherry picked from commit 03dac3e37993801dab4418087bfedacce0526e66)
(cherry picked from commit da2b630c12ec074673dfc646b2055a31b0d8d6d9)