NetBSD re-synchronization of the source tree

This brings our tree to NetBSD 7.0, as found on -current on the
10-10-2015.

This updates:
 - LLVM to 3.6.1
 - GCC to GCC 5.1
 - Replace minix/commands/zdump with usr.bin/zdump
 - external/bsd/libelf has moved to /external/bsd/elftoolchain/
 - Import ctwm
 - Drop sprintf from libminc

Change-Id: I149836ac18e9326be9353958bab9b266efb056f0

lib/libc/include/env.h

@@ -1,4 +1,4 @@
-/*	$NetBSD: env.h,v 1.2 2010/11/14 22:04:36 tron Exp $	*/
+/*	$NetBSD: env.h,v 1.3 2015/01/20 18:31:25 christos Exp $	*/
 
 /*-
  * Copyright (c) 2010 The NetBSD Foundation, Inc.
@@ -56,11 +56,7 @@ __writelockenv(void)
 }
 
 static __inline bool
-#if defined(__minix)
 __unlockenv(void)
-#else /* Bug-to-bug compatibility? LSC: FIXME We should upstream that. */
-__unlocklockenv(void)
-#endif /* defined(__minix) */
 {
 	return true;
 }