cps2ds sometimes introduces ownerless Vars

[leissa]

I'm 99% sure it's also broken on current master but most of the time we won't notice because the ownerless Var will be optimized away. However, we sometimes have the effect on master that things break as soon as you print sth. This is the reason for this. I fixed one issue in #269 but this one here remains: `

./bin/thorin ../lit/direct/ad_mem.thorin.disabled2 -p clos    

Speaking of this: Why is there also lit/direct/ad_mem.thorin.disabled?

[leissa]

• removed old ad_mem.thorin.disabled and moved ad_mem.thorin.disabled2 -> ad_mem.thorin.disabled
• there is also ad_mem2.thorin.disabled. do we need this?
• both tests are a mess and we should probably come up with simpler tests that provoke the bug