fix non-NUCSYN build by adding missing #ifdef NUCSYN .. #endif

src/nucsyn/nucsyn_remove_mass_from_surface.c

 #include "../binary_c.h"
 
+#ifdef NUCSYN
+
 void nucsyn_remove_mass_from_surface(
 #if defined DEBUG && DEBUG > 0
     struct stardata_t * stardata,
@@ -35,3 +37,5 @@ void nucsyn_remove_mass_from_surface(
         *allocated = FALSE;
     }
 }
+
+#endif //NUCSYN