Long overdue MFC r284377:

Long overdue MFC r284377:
  NetBSD commit log:
    Use a constant array for the MIB. Newer LLVM decided that mib[] warranted
    stack protections, with the obvious crash after the setup was done.
    As a positive side effect, code size shrinks a bit.

  I'm not sure why this hasn't bitten us yes, but it is certainly possible and
  there are no real drawbacks to this change anyway.

  Submitted by: pfg
  Obtained from:        NetBSD

git-svn-id: svn://svn.freebsd.org/base/stable/10@288105 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f