Bluetooth: hci_vhci: Fix calling hci_{suspend,resume}_dev

Defer calls to hci_{suspend,resume}_dev to work so it doesn't block the
processing of the events.

Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>