Merge branch 'maint'

Merge branch 'maint'

* maint:
  cosmetics: rename t/ax/test-runner => t/ax/runtest
  fixup: another "make recheck" failure with BSD make
  test runner: work correctly in VPATH setups
  compat: automake should define $(mkdir_p), for backward compatibility
  coverage: test that AM_PROG_MKDIR_P and $(mkdir_p) still works
  tests init: don't automatically re-execute tests with a POSIX shell
  yacc tests: fix spurious failure with parallel make
  tests: ignore minor 'recheck' regression for BSD make
  tests: don't clutter the top-level dir with temporary test directories
  tests: avoid spurious failures when @MKDIR_P@ points to "install-sh -d"
  lisp: better support of VPATH builds
  news: fixlets and updates

+ Extra non-trivial edits:

* NEWS: State that $(mkdir_p) is still provided as an alias to
$(MKDIR_P), for (partial) backward-compatibility.

Signed-off-by: Stefano Lattarini <stefano.lattarini@gmail.com>