1.3.5 on Solaris

[David Shaw]

Matt Selsky noted a build problem under Solaris.  It's a piece of
leftover debug code.  Here's the fix:

Index: unsetenv.c
===================================================================
RCS file: /cvs/gnupg/gnupg/util/unsetenv.c,v
retrieving revision 1.1
diff -r1.1 unsetenv.c
29c29
< unsetenv2 (const char *name)
---
> unsetenv(const char *name)