The ISO Interval on CIS Established Event uses 1.25 ms slots:

    BLUETOOTH CORE SPECIFICATION Version 5.3 | Vol 4, Part E
    page 2304:

      Time = N * 1.25 ms

In addition to that this always update the QoS settings based on CIS
Established Event.
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>