One more missing prototype

[Andreas Jaeger]

Here's a final missing prototype which I considered
significant [1]:

string/envz.c (and string/Versions) exports `envz_remove' but it's not
in envz.h.  Should we export it?

Andreas


Footnotes: 
[1]  There're also missing prototypes for internal functions like
     __libc_freeres but I didn't consider these.
-- 
 Andreas Jaeger   aj@arthur.rhein-neckar.de    jaeger@informatik.uni-kl.de
  for pgp-key finger ajaeger@aixd1.rhrk.uni-kl.de