Remove corosync-fplay

Libqb now ships with qb-blackbox command doing same job as
corosync-fplay. It doesn't make sense to maintain two versions of same
utility so corosync-fplay can go. corosync-blackbox command now calls
directly qb-blackbox.

Signed-off-by: Jan Friesse <jfriesse@redhat.com>
Reviewed-by: Steven Dake <sdake@redhat.com>