Bluetooth: Fix possible infinite recursion of btusb_reset

The function enters infinite recursion if the HCI device doesn't support
GPIO reset: btusb_reset -> hdev->reset -> vendor_reset -> btusb_reset...

btusb_reset shouldn't call hdev->reset after commit f07d4780
("Bluetooth: Get rid of cmd_timeout and use the reset callback")

Fixes: f07d4780 ("Bluetooth: Get rid of cmd_timeout and use the reset callback")
Signed-off-by: Hsin-chen Chuang <chharry@chromium.org>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>