st/nine: generate resource if doesn't exist when used

Hack necessary for the time being.

Fixes Divinity: Original Sin, Blur, Prototype 2.

Acked-by: Axel Davy <axel.davy@ens.fr>
Signed-off-by: Stanislaw Halik <sthalik@misaki.pl>
Merge pull request #40 from sthalik/hack-resource

fix resource not generated in time