Add pthread_condattr_init/destroy/setpshared/getpshared

Note that this does not change the implementation of conditional variables
which still use shared futexes, independent on the flags being selected.

This will be fixed in a later patch, once our system is modified to use
pthread_condattr_setpshared(attr, PTHREAD_PROCESS_SHARED) properly.

Change-Id: I935de50964cd41f97a13dbfd6626d3407b0406c3
3 files changed