Bluetooth: btrtl: Ask ic_info to drop firmware

Some un-support wakeup platforms keep USB power and suspend signal
is coming late, this makes Realtek some chip keep its firmware,
and make it never load new firmware.

So use vendor specific HCI command to ask them drop its firmware after
system shutdown or resume.

Signed-off-by: Hilda Wu <hildawu@realtek.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>