Bluetooth: Perform a power cycle when receiving hardware error event

When receiving a HCI Hardware Error event, the controller should be
assumed to be non-functional until issuing a HCI Reset command.

The Bluetooth hardware errors are vendor specific and so add a
new hdev->hw_error callback that drivers can provide to run extra
code to handle the hardware error.

After completing the vendor specific error handling perform a full
reset of the Bluetooth stack by closing and re-opening the transport.

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