Bluetooth: add hci_connect_le_scan

Currently, when trying to connect to already paired device that just
rotated its RPA MAC address, old address would be used and connection
would fail. In order to fix that, kernel must scan and receive
advertisement with fresh RPA before connecting.

This patch adds hci_connect_le_scan with dependencies, new method that
will be used to connect to remote LE devices. Instead of just sending
connect request, it adds a device to whitelist. Later patches will make
use of this whitelist to send conenct request when advertisement is
received, and properly handle timeouts.

Signed-off-by: Jakub Pawlowski <jpawlowski@google.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>