libpthread missing pthread_mutexattr_setpshared, pthread_condattr_setpshared

[Thomas Klausner]

Hi!

The POSIX functions pthread_condattr_setpshared and
pthread_mutexattr_setpshared are needed by libxshmfence, which will be
part of a future xserver. They are currently missing in our
libpthread. Can someone please implement them?
 Thomas