$NetBSD: patch-autoconf_os,v 1.1.1.1 2019/08/24 22:09:16 alnsn Exp $

Add NetBSD, pull request https://github.com/SRI-CSL/yices2/pull/134

--- autoconf/os.orig	2018-10-26 21:33:09.000000000 +0000
+++ autoconf/os
@@ -13,6 +13,8 @@ if eval 'uname > /dev/null 2> /dev/null'
       echo "mingw";;
     FreeBSD*)
       echo "freebsd";;
+    NetBSD*)
+      echo "netbsd";;
     *)
       echo "unix";;
   esac