Bluetooth: hci_sync: Rework hci_suspend_notifier

This makes hci_suspend_notifier use the hci_*_sync which can be
executed synchronously which is allowed in the suspend_notifier and
simplifies a lot of the handling since the status of each command can
be checked inline so no other work need to be scheduled thus can be
performed without using of a state machine.

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