rename switch_socket_create_pollfd to switch_socket_create_pollset, add switch_socket_create_pollfd that really creates a pollfd out of a socket, expose switch_pollset_poll and switch_pollset_remove

git-svn-id: http://svn.freeswitch.org/svn/freeswitch/trunk@16683 d0543943-73ff-0310-b7d9-9358b9ac24b2