ctdb-daemon: Drop handling of ban control sent to unexpected node

ctdb-daemon: Drop handling of ban control sent to unexpected node

The banning code caters for the case where the node specified in the
bantime data is not the node receiving the control.  This never
happens.  There are 2 places where ctdb_ctrl_set_ban() is called: the
ctdb CLI tool and the recovery daemon.  Both pass the same node in the
bantime data that they are sending the control to.  There are no plans
to do anything more elaborate, so just delete the handling of this
special case.

Signed-off-by: Martin Schwenke <martin@meltin.net>
Reviewed-by: Amitay Isaacs <amitay@gmail.com>