Move TAILQ initialization to files where they are used.

Move TAILQ initialization to files where they are used.

These priv-sep daemons all follow a similar design and use TAILQs
for tracking control process connections. In most cases, the TAILQs
are initialized separate from where they are used. Since the scope
of use is generally confined to a specific control process file,
this commit also removes any extern definitions and exposing the
TAILQ structures to other compilation units.

ok bluhm@, tb@