- Add --localstatedir=/var to _LATE_CONFIGURE_ARGS (like --mandir) but not
  when CONFIGURE_ARGS already sets it.  (GNU configure scripts set it to
  PREFIX/var when PREFIX != /usr.)
- Add --localstatedir="${PREFIX}/var" to CONFIGURE_ARGS in some ports so
  they aren't affected by this change (for now at least).  This commit is
  meant to ensure that new ports don't make the same mistake.

- games/acm: the configure script in this port is very old; instead of
  patching it more, just replace GNU_CONFIGURE with HAS_CONFIGURE.
- irc/charybdis: it already used /var but adding --localstatedir=/var
  changed the behaviour of the configure script; adjust the port to this.

PR:		199506
Exp-run by:	antoine
Approved by:	portmgr (antoine)