Move module object inside MODULE_INFO

This allows modules to only expose one entry point with a consistent
signature. In the future, this could be used to implement declarations of
module parameters.

include/maxscale/dcb.h

@@ -326,7 +326,7 @@ typedef enum
 void dcb_global_init();
 
 int dcb_write(DCB *, GWBUF *);
-DCB *dcb_accept(DCB *listener, GWPROTOCOL *protocol_funcs);
+DCB *dcb_accept(DCB *listener);
 DCB *dcb_alloc(dcb_role_t, struct servlistener *);
 void dcb_free(DCB *);
 void dcb_free_all_memory(DCB *dcb);

include/maxscale/filter.hh

@@ -193,7 +193,7 @@ protected:
  * The plugin function @c GetModuleObject is then implemented as follows:
  *
  * @code
- * extern "C" FILTER_OBJECT *GetModuleObject()
+ * extern "C" MODULE_INFO* GetModuleObject()
  * {
  *     return &MyFilter::s_object;
  * };

include/maxscale/modinfo.h

@@ -86,6 +86,7 @@ typedef struct
     MODULE_VERSION  api_version;
     const char     *description;
     const char     *version;
+    void           *module_object;
 } MODULE_INFO;
 
 MXS_END_DECLS