bug#17659: 24.3.90; C-x 8 ? displays help instead of inserting INVERTED QUESTION MARK

[Drew Adams]

> > ? is bound in iso-transl-ctl-x-8-map but oddly the ? (help-char) takes
> > precedence. Stefan, any idea where to look to fix it?
> 
> BTW, maybe it was obvious to someone, but it wasn't to me, so I'll
> mention that this is a regression w.r.t 24.3 and it is caused by the
> change documented in NEWS:
> 
> *** The key `?' now describes prefix bindings, like `C-h'.

See also bug #16617.