[x265] [PATCH 4 of 7] threadpool.cpp: window specific header 'winnt.h'

[praveen at multicorewareinc.com]

# HG changeset patch
# User Praveen Tiwari <praveen at multicorewareinc.com>
# Date 1463738737 -19800
#      Fri May 20 15:35:37 2016 +0530
# Node ID 598afbba907e06563ac08c0058abdbd7ba50d5d8
# Parent  ab1b27a1712d581c32b007f0f72e482f4a83905d
threadpool.cpp: window specific header 'winnt.h'

diff -r ab1b27a1712d -r 598afbba907e source/common/threadpool.cpp
--- a/source/common/threadpool.cpp	Fri May 20 15:35:37 2016 +0530
+++ b/source/common/threadpool.cpp	Fri May 20 15:35:37 2016 +0530
@@ -27,7 +27,10 @@
 #include "threading.h"
 
 #include <new>
+
+#if _WIN32
 #include <winnt.h>
+#endif // _WIN32
 
 #if X86_64