Bluetooth: mgmt: Clear EIR data when disabling SSP

EIR shouldn't be enabled if SSP isn't enabled. This patch adds the
clearing of EIR data when disabling SSP and restores the data when SSP
is re-enabled.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Acked-by: Marcel Holtmann <marcel@holtmann.org>