Fix VS2015 syntax error with ZMQ_DEPRECATED macro.

SylvainCorlay · sigiesec · commit deb1617ebc73 · 2020-10-05T14:50:03.000+02:00
diff --git a/zmq.hpp b/zmq.hpp
@@ -61,7 +61,7 @@
 #define ZMQ_CPP17
 #endif
 
-#if defined(ZMQ_CPP14)
+#if defined(ZMQ_CPP14) && !defined(_MSC_VER)
 #define ZMQ_DEPRECATED(msg) [[deprecated(msg)]]
 #elif defined(_MSC_VER)
 #define ZMQ_DEPRECATED(msg) __declspec(deprecated(msg))
