Disable FSX utiltiy class test for anything non-FSX because it creates
a repository and that may or may not fail depending on test parameters.

* subversion/tests/libsvn_fs_x/fs-x-pack-test.c
  (test_reps): run for 1.9+ FSX only

git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1512319 13f79535-47bb-0310-9956-ffa450edef68