Set compiler check: make sure MASTER and SLAVE defines are not set at the same time.

src/hwapi.cpp

@@ -56,11 +56,13 @@ hwapi::hwapi(QWidget *parent) : QObject(parent)
 
         myDatif = new T_datif();    // für die  CAslave-Lib auskommentieren!
 
-#else
+#endif
+
+#ifdef THIS_IS_CA_SLAVE
 
 #ifdef THIS_IS_CA_MASTER
 #error "MASTER LIB COMPILED INTO MASTER"
-#endif	
+#endif
 
 #endif