Merge branch 'tests-features' of https://github.com/rudimeier/util-linux

* 'tests-features' of https://github.com/rudimeier/util-linux:
  tests: style Makefile and make output
  tests: allow to add or override test suite options
  tests: add exit case "KNOWN FAILED"
  tests: fix var names
  tests: allow test options to be overridden by env
  tests: call ts_init_env as early as possible