Correctness fixes for NaCl and other platforms.

Add missing includes of stdio.h, and prefer |IN6ADDR_ANY_INIT| to
|in6addr_any|.

Change-Id: Ia6663ecd6f87008cb82979ef65620a55d8c9405b
Reviewed-on: https://boringssl-review.googlesource.com/11626
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>

tool/rand.cc

diff --git a/tool/rand.cc b/tool/rand.cc
index 3701748..b442e0d 100644
--- a/tool/rand.cc
+++ b/tool/rand.cc
@@ -16,6 +16,7 @@
 #include <vector>
 
 #include <stdint.h>
+#include <stdio.h>
 #include <stdlib.h>
 
 #include <openssl/rand.h>