mail/dot-forward: include errno.h for errno

errno must be accessed by a macro from errno.h.

mail/dot-forward/Makefile

@@ -1,6 +1,6 @@
 PORTNAME=	dot-forward
 PORTVERSION=	0.71
-PORTREVISION=	1
+PORTREVISION=	2
 CATEGORIES=	mail
 MASTER_SITES=	http://cr.yp.to/software/
 

mail/dot-forward/files/patch-error.h

@@ -0,0 +1,11 @@
+--- error.h.orig
++++ error.h
+@@ -1,7 +1,7 @@
+ #ifndef ERROR_H
+ #define ERROR_H
+ 
+-extern int errno;
++#include <errno.h>
+ 
+ extern int error_intr;
+ extern int error_nomem;