Updated the config file for linux x86_64 architectures since all linux systems...

Updated the config file for linux x86_64 architectures since all linux systems have Qt5.6.0 built and installed in the local/v006 area.

git-svn-id: http://subversion.wr.usgs.gov/repos/prog/isis3/branches/v006LibrariesV2@6737 41f8697f-d340-4b68-9986-7bafba869bb8