hook_filter_info() settings-callback args are misdocumented

API lists the arguments passed to 'settings callback' variously as "form_state, filter, defaults, format, filters" or "form, form_state, filter, defaults".

The correct argument order, as seen in filter.module's own code, is "form, form_state, filter, format, defaults". (Try to say that fast. ;) )

As this is a hook documentation, the patch will not need to be committed by a maintainer.