Throwing monsters into walls doesn't cause damage

[Grond]

When you throw a monster into a wall (assuming you have the requisite strength to move them that far) they don't take damage and a "the -foo- bumps into a wall" message is displayed, as if they had attempted to move normally into the wall.

[adom-admin]

Fixed for ADOM II 0.3.1. Please send your real name to creator(at)ancientdomainsofmystery.com for it to be included in the credits. (If you were already asked to do so you can ignore this message. Please include a reference to the bug or RFE you are credited for.)