🚀 go-pugleaf

In fileutils 3.3, lib/xgetcwd.c does not compile on my IBM RT running
4.3 BSD, since <errno.h> does not declare `errno'.

Here is a diff.  This is the way rms once suggested errno be declared.

Sat Jul 25 11:34:50 1992  Karl Berry  (karl@fosse)

        * xgetcwd.c (errno) [!errno]: declare as int, for the benefit of
          those systems (e.g., 4.3 BSD) which do not declare it in <errno.h>.

*** ./ORIG/xgetcwd.c	Mon Jul 13 21:37:16 1992
--- ./xgetcwd.c	Sat Jul 25 11:30:09 1992
***************
*** 19,24 ****
--- 19,27 ----
  
  #include <stdio.h>
  #include <errno.h>
+ #ifndef errno
+ extern int errno;
+ #endif
  #include <sys/types.h>
  #include "pathmax.h"