Fix failing itk system spec on RedHat

The itk spec test failed on RedHat instead of skipping it. This
commit corrects that behavior.
Fixed failing itk system spec on RedHat
Merge pull request #349 from blkperl/fix_system_spec_on_rhel

Fix failing itk system spec on RedHat
Revert "Merge pull request #349 from blkperl/fix_system_spec_on_rhel"

This reverts commit 714777ef6dedbccca8ada86a80fba009a93aebd7, reversing
changes made to 0b47f7ccc6a7d348ac29c92c0ea3b0a98a6cdd41.
Merge pull request #351 from ptomulik/itk_redhat

Fixed failing itk system spec on RedHat