Bluetooth: ath3k: use usb_control_msg_send() and usb_control_msg_recv()

Bluetooth: ath3k: use usb_control_msg_send() and usb_control_msg_recv()

The usb_control_msg_send() and usb_control_msg_recv() calls can return
an error if a "short" write/read happens, and they can handle data off
of the stack, so move the driver over to using those calls instead,
saving some logic when dynamically allocating memory.

Cc: Marcel Holtmann <marcel@holtmann.org>
Cc: Johan Hedberg <johan.hedberg@gmail.com>
Link: https://lore.kernel.org/r/20200914153756.3412156-11-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>