MFC r295202:

MFC r295202:

 Try to fix a bug introduced in r228623 (head).
 We started to copy the ifa_msghdr as otherwise platforms with strict
 alignment would break.  It is unclear to me if there's also a problem with
 access to the address list following the structure.
 However we never copied the address list after the structure and thus are
 pointing at random memory.  For now just use a pointer to the original
 memory for accessing the address list making it at least work on
 platforms with weak memory access.

 PR:                   195445
 Reported by:          wolfgang lyxys.ka.sub.org
 Tested by:            wolfgang lyxys.ka.sub.org (x86)

Approved by:		re (marius)

git-svn-id: svn://svn.freebsd.org/base/stable/10@295386 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f