Bluetooth: btrtl: add support for the RTL8723BS and RTL8723DS chips

The Realtek RTL8723BS and RTL8723DS chipsets are SDIO wifi chips. They
also contain a Bluetooth module which is connected via UART to the host.

Realtek's userspace initialization tool (rtk_hciattach) differentiates
these two via the HCI version and revision returned by the
HCI_OP_READ_LOCAL_VERSION command.
Additionally we apply these checks only the for UART devices. Everything
else is assumed to be a "RTL8723B" which was originally supported by the
driver (communicating via USB).

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Jeremy Cline <jeremy@jcline.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>