Bluetooth: Fix length for Read Local OOB Extended Data respone packet

The length of the respone packet for Read Local OOB Extended Data
command has a calculation error. In case LE Secure Connections support
is not enabled, the actual response is shorter. Keep this in mind and
update the value accordingly.

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