Set WINVER to Windows 2000 like in config.w32.h.in

Author: KalleZ

win32/build/config.w32

@@ -114,7 +114,7 @@ DEFINE("BASE_INCLUDES", "/I . /I main /I Zend /I TSRM /I ext ");
 
 // CFLAGS for building the PHP dll
 DEFINE("CFLAGS_PHP", "/D _USRDLL /D PHP5DLLTS_EXPORTS /D PHP_EXPORTS \
-/D LIBZEND_EXPORTS /D TSRM_EXPORTS /D SAPI_EXPORTS /D WINVER=0x400");
+/D LIBZEND_EXPORTS /D TSRM_EXPORTS /D SAPI_EXPORTS /D WINVER=0x500");
 
 DEFINE('CFLAGS_PHP_OBJ', '$(CFLAGS_PHP) $(STATIC_EXT_CFLAGS)');