fix module setenv's dependencies

[Bruno Haible]

unsetenv.c includes <unistd.h> unconditionally. Therefore this module
must depend on 'unistd'. (Even though setenv.c uses HAVE_UNISTD_H, for
reasons explained in the other mail.)

2006-07-29  Bruno Haible  <address@hidden>

        * modules/setenv (Depends-on): Add unistd.

*** modules/setenv      29 Sep 2004 22:10:44 -0000      1.8
--- modules/setenv      29 Jul 2006 15:32:10 -0000
***************
*** 11,16 ****
--- 11,17 ----
  Depends-on:
  allocsa
  alloca-opt
+ unistd
  
  configure.ac:
  gt_FUNC_SETENV