Lycanthrope's berserk behaviour doesn't work

A lycanthrope is supposed to go beserk on occasion and
repeatedly hit its opponent without conscious will. While
you get the various "Grrrrr!" messages, the repeat hits
don't work.

This is due to a confusion in attack() which believes
that hmonas() returns TRUE if the opponent is still alive,
whereas hmonas() actually returns TRUE if you hit.

The next miss will thus cancel beserk mode.