Supports sqlite

The updater did not run with a sqlite database backend. It was simply
not registered and the MySQL schema is translated just fine by
MediaWiki.

Bug: 67296
Change-Id: Iced2c6a85752e64c01a296a85d0b1339503b15a5
(cherry picked from commit 46934d163c7463158ffbd1e87800eef2a40788ae)