Bluetooth: Filter list of supported commands/events for untrusted users

When the user of the management interface is not trusted, then it only
has access to a limited set of commands and events. When providing the
list of supported commands and events take the trusted vs untrusted
status of the user into account and return different lists.

This way the untrusted user knows exactly which commands it can
execute and which events it can receive. So no guesswork needed.

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