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

libexec/ftpd/pfilter.c

@@ -0,0 +1,24 @@
+#include <stdio.h>
+#include <blacklist.h>
+
+#include "pfilter.h"
+
+static struct blacklist *blstate;
+
+void
+pfilter_open(void)
+{
+	if (blstate == NULL)
+		blstate = blacklist_open();
+}
+
+void
+pfilter_notify(int what, const char *msg)
+{
+	pfilter_open();
+
+	if (blstate == NULL)
+		return;
+
+	blacklist_r(blstate, what, 0, msg);
+}