Bluetooth: Add support for handling LE Direct Advertising Report events

When the controller sends a LE Direct Advertising Report event, the host
must confirm that the resolvable random address provided matches with
its own identity resolving key. If it does, then that advertising report
needs to be processed. If it does not match, the report needs to be
ignored.

This patch adds full support for handling these new reports and using
them for device discovery and connection handling. This means when a
Bluetooth controller supports the Extended Scanner Filter Policies, it
is possible to use directed advertising with LE privacy.

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