Bluetooth: Limit acceptable link key types to only supported ones

The link keys that are loaded by userspace during controller setup
should be limited to actual valid and supported types. With the
support for Secure Connections, it is limited to types 0x00 - 0x08
at the moment. Reject any other link key types.

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