Log Message:
mlterm: pull an upstream patch for 3.9.0.

Also put misc pkgsrc tweaks:
- Disable SPECIAL_PERMS for mlterm.  It was required for utmp support
  only on ancient systems that have none of pututxline(3), setutent(3),
  or addToUtmp(3) but have to use logwtmp(3) or open system's _PATH_UTMP
  or _PATH_WTMP file directly to update utmp entries, but no easy way
  to statically identify them per OS and version basis.
- Add hacks.mk to avoid gcc SIGSEGV on NetBSD/sh3 9.0 (PR/55265)
- Appease several pkglint warnings/errors.

Bump PKGREVISION.