Add missing register_translator() for nova driver

These should have been added in: a1edc74f1001b6ed0b8497cdeec29f784e428762
but was left out. I'll tests in a later patch but would like to merge this
to fix the nova driver for get_schema()

Change-Id: Ib0244fd7002bc29cbe7062585e015985910c0f62
Merge "Add missing register_translator() for nova driver"