chrony: fix build failure due to missing inclusion of util.h

During build package stops with linker error:
hash_intmd5.o: In function `HSH_Hash':
hash_intmd5.c:(.text+0x963): undefined reference to `MIN'

This is due to missing util.h inclusion.
util.h contains MIN() macro definition.

Add upstream patch:
https://git.tuxfamily.org/chrony/chrony.git/commit/?id=948ecf84314f78da82e0e2b07b6570ca9cff86c8
to add #include "util.h" in hash_intmd5.c

Fixes:
http://autobuild.buildroot.net/results/8f0/8f0d53b1d5a899e56540c859b908cbc1eaa223d5/
http://autobuild.buildroot.net/results/3c6/3c609f94aff182c9ab47ef8ec4b9de03a4d20ffb/
http://autobuild.buildroot.net/results/f1f/f1fcae399fb640c19cf88c9333a92cbfab547932/

Signed-off-by: Giulio Benetti <giulio.benetti@micronovasrl.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/chrony/0002-hash-include-util.h-for-MIN-macro.patch

@@ -0,0 +1,28 @@
+From 948ecf84314f78da82e0e2b07b6570ca9cff86c8 Mon Sep 17 00:00:00 2001
+From: Miroslav Lichvar <mlichvar@redhat.com>
+Date: Thu, 20 Sep 2018 15:01:16 +0200
+Subject: [PATCH] hash: include util.h for MIN macro
+
+The hash_intmd5.c file inadvertently relied on the system headers to
+provide the MIN macro, but it is missing with some libc implementations.
+
+Signed-off-by: Giulio Benetti <giulio.benetti@micronovasrl.com>
+---
+ hash_intmd5.c | 1 +
+ 1 file changed, 1 insertion(+)
+
+diff --git a/hash_intmd5.c b/hash_intmd5.c
+index 0b60f9b..49da1cf 100644
+--- a/hash_intmd5.c
++++ b/hash_intmd5.c
+@@ -29,6 +29,7 @@
+ #include "sysincl.h"
+ #include "hash.h"
+ #include "memory.h"
++#include "util.h"
+ 
+ #include "md5.c"
+ 
+-- 
+2.17.1
+