BUG: makeCGAL with specified version installs into the wrong directory

- was applied precision-specific information:
    * instead of linux64Gcc [correct]
    * was using  linux64GccInt32 [wrong]

  This problem does not the regular use where CGAL is defined from
  etc/config.sh/CGAL since the CGAL_ARCH_PATH specified there was properly
  respected.