Before touching 'locale-check.skip', ensure parent exists

This patch ensures '/var/lib/cloud/instance' exists before attempting to create
'/var/lib/cloud/instance/locale-check.skip'. It does not create or check for
'/var/lib/cloud', but I have not known that folder to disappear.

Bug: 50965
Change-Id: I65f44aab691cb0d9404d0163003bc6edd47f92e7