Bluetooth: Fix checking for proper key->master value in Load LTKs

The allowed values for the key->master parameter in the Load LTKs
command are 0x00 and 0x01. If there is a key in the list with some other
value the command should fail with a proper invalid params response.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>