Bluetooth: Handle Inquiry Cancel error after Inquiry Complete

After sending Inquiry Cancel command to the controller, it is possible
that Inquiry Complete event comes before Inquiry Cancel command complete
event. In this case the Inquiry Cancel command will have status of
Command Disallowed since there is no Inquiry session to be cancelled.
This case should not be treated as error, otherwise we can reach an
inconsistent state.

Example of a btmon trace when this happened:

< HCI Command: Inquiry Cancel (0x01|0x0002) plen 0
> HCI Event: Inquiry Complete (0x01) plen 1
        Status: Success (0x00)
> HCI Event: Command Complete (0x0e) plen 4
      Inquiry Cancel (0x01|0x0002) ncmd 1
        Status: Command Disallowed (0x0c)

Signed-off-by: Sonny Sasaka <sonnysasaka@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>