memory-device: not necessary to use goto for the last check

We are already at the last condition check.

Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190730003740.20694-2-richardw.yang@linux.intel.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>