bug#66057: (ice-9 match) allows invalid usages of ... or ..1

Hi,

After attempting the following:

--8<---------------cut here---------------start------------->8---
(match (string-split "./Bootloaders/Printer/Documentation/html" #\/)
                                 (("." path ..1 "Documentation" "html")
                                  (pk 'path path)))

=> ;;; (path "Bootloaders")

Expected (and works with '...'): 
;;; (path "Bootloaders" "Printer")
--8<---------------cut here---------------end--------------->8---

and asking about it in #scheme or #guile, it seems the '..1' and '...'
patterns *must* be used strictly to match at the end of lists, but this
isn't explicitly mentioned in the manual, and even works for ... but not
for ..1, which is inconsistent/econfusing.

It was suggested by Zipheir in #scheme that Guile should return a syntax
error when ..1 or ... are used somewhere else than at the end of a list.
It seems a good suggestion.

-- 
Thanks,
Maxim