POLL: Allow modifying POLLIN/POLLOUT state in another thread.
POLL: Allow modifying POLLIN/POLLOUT state in another thread.

while the main thread is blocked in poll system call.

(ported from corosync)

Author: Steven Dake <8638f3fce5db0278cfbc239bd581dfc00c29ec9d@redhat.com>
Signed-off-by: Angus Salkeld <86b65304d27d8de73dd7d624c33df7e088f8d94b@redhat.com>

davidvossel/libqb,davidvossel/libqb,kgaillot/libqb,gao-yan/libqb,ClusterLabs/libqb,rubenk/libqb,kgaillot/libqb,ClusterLabs/libqb,ClusterLabs/libqb,gao-yan/libqb,rubenk/libqb,kgaillot/libqb