FSCORE-252 Core NetBSD features are disabled if _XOPEN_SOURCE is defined

git-svn-id: http://svn.freeswitch.org/svn/freeswitch/trunk@10755 d0543943-73ff-0310-b7d9-9358b9ac24b2

src/include/switch.h

@@ -54,7 +54,7 @@
 #define FREESWITCH_ITAD "543"
 #define __EXTENSIONS__ 1
 #ifndef MACOSX
-#if !defined(_XOPEN_SOURCE) && !defined(__OpenBSD__)
+#if !defined(_XOPEN_SOURCE) && !defined(__OpenBSD__) && !defined(__NetBSD__)
 #ifndef __cplusplus
 #define _XOPEN_SOURCE 600
 #endif