Bluetooth: hci_sync: Set HCI_CMD_DRAIN_WORKQUEUE during device close

Since hci_dev_close_sync() can now be called during the reset path, we
should also set HCI_CMD_DRAIN_WORKQUEUE. This avoids queuing timeouts
while the hdev workqueue is being drained.

Fixes: 877afadad2dc ("Bluetooth: When HCI work queue is drained, only queue chained work")
Signed-off-by: Heitor Alves de Siqueira <halves@igalia.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>