userland via routing socket or sysctl. This eliminates the following
KAME-specific sin6_scope_id handling routine from each userland utility:
sin6.sin6_scope_id = ntohs(*(u_int16_t *)&sin6.sin6_addr.s6_addr[2]);
This behavior can be controlled by net.inet6.ip6.deembed_scopeid. This is
set to 1 by default (sin6_scope_id will be filled in the kernel).
Reviewed by: bz