Bluetooth: Use zero timeout for immediate scheduling

There's no point in passing a "small" timeout to queue_delayed_work() to
try to get the callback faster scheduled. Passing 0 is perfectly valid
and will cause a shortcut to a direct queue_work().

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>