Provide dummy implementations of pthread functions like mutex operations
to enable libraries to be used in both thread-aware and non-threaded programs.

This package is derived from Matthias Drochner's stubs package for older
versions of NetBSD.  The intent is to use this with libX11 (or xcb), or perhaps
elsewhere in pkgsrc as needed.  Included is a pkg-config file that is
identical to the libpthread-stubs package from libxcb.  This library
contains more functions and no GNU autoconf cruft.  Great taste, less
filling! ;)