Bump overlay version number.

Forces the overlays.xml file to be ignored and overwritten,
which makes the default overlay be used in all cases, rather
than no overlay.

Fixes: 37788042
Test: manual, removed some overlays in an update and observed that
the proper overlay was used.

Change-Id: Ieda4485f3e64ae627476e1fdcfc5af6cdcca0c15