PATCH: [perl #133649] fails on OpenBSD-6.4 unthreaded

PATCH: [perl #133649] fails on OpenBSD-6.4 unthreaded

OpenBSD has a (perfectly legal) different syntax for the string
parameter to setlocale(), so the failing tests are not actually valid on
that platform.  Rather than go to the significant effort to create a
Configure probe to find out what platforms use what syntax, simply skip
these on this platform.  The tests aren't skipped if built with threads,
as they actually help make sure that the code that deals with different
syntaxes for thread-safe handling of locales works in the face of
different syntaxes