Modify OPERATION_FAILED and INTERNAL_ERROR error codes to
use DEVICE_MISSING instead for failures associated with the
inability to find the device. This makes it easier for consumers
to key off the error code rather than the error message.
Signed-off-by: NChen Hanxiao <chenhanxiao@gmail.com>
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>