[QAT] r334119: 4x leftovers

[Ports-QAT]

Miscellaneous fixes.

- Add desktop-file-utils to the USES list, bumping PORTREVISION.

- Force USE_GCC only on OSVERSION < 1000024, to avoid running into
  a libc++/libstdc++ mismatch in glibmm-2.4 on FreeBSD 10
  (which caused linker troubles in the Glib:: namespace due to
  libc++-based different mangling - glibmm is compiled to use libc++
  on 10-STABLE, so we cannot USE_GCC there).

- Force disable OpenMP option on non-GCC systems, because clang does
  not yet support it.

- In order to be able to use clang, force ipsharpen.cc to be compiled
  with -O1 only because -O2 or higher optimization levels lead to
  excessive compile times, so long that I never waited for the compile
  to complete (over 10 minutes on a Phenom II at 2.5 GHz).

- Quench unused-command-line-arguments warnings on clang.

This should fix the compile on 10-STABLE and HEAD.

Whether the software actually works I cannot currently test due to
lack of a full desktop install of 10-STABLE.
---------------------------------------------------------------------

  Build ID:          20131117200800-49879
  Job owner:         mandree at FreeBSD.org
  Buildtime:         82 minutes
  Enddate:           Sun, 17 Nov 2013 21:29:35 GMT

  Revision:          r334119
  Repository:        https://svnweb.freebsd.org/ports?view=revision&revision=334119

---------------------------------------------------------------------

    Port:            graphics/rawtherapee 4.0.11_2

      Buildgroup:     8.4-QAT/amd64
      Buildstatus:   LEFTOVERS
      Log: https://qat.redports.org//~mandree@FreeBSD.org/20131117200800-49879-227852/rawtherapee-4.0.11_2.log

      Buildgroup:     8.4-QAT/i386
      Buildstatus:   LEFTOVERS
      Log: https://qat.redports.org//~mandree@FreeBSD.org/20131117200800-49879-227853/rawtherapee-4.0.11_2.log

      Buildgroup:     9.2-QAT/amd64
      Buildstatus:   LEFTOVERS
      Log: https://qat.redports.org//~mandree@FreeBSD.org/20131117200800-49879-227854/rawtherapee-4.0.11_2.log

      Buildgroup:     9.2-QAT/i386
      Buildstatus:   LEFTOVERS
      Log: https://qat.redports.org//~mandree@FreeBSD.org/20131117200800-49879-227855/rawtherapee-4.0.11_2.log


--
Buildarchive URL: <https://qat.redports.org/buildarchive/20131117200800-49879>
redports <https://qat.redports.org/>