fix #H7039 - autodescribe of hallucinated statue

fix #H7039 - autodescribe of hallucinated statue

Having the autodescribe feature enabled and moving the cursor onto
a statue yields "statue of a <mon>" under normal circumtances, but
when done while hallucinating the feedback was just blank (because
the lookat() code couldn't find any monster at statue's location).
Now it will be "<random mon>" (not "statue of a <random mon>")
instead, same as when moving cursor over glyphs of actual monsters.