efl/eo: Fix Doxygen markup to prevent a warning

Summary:
The closing @} for the main Eo group is inside the #ifdef
EFL_BETA_API_SUPPORT block, so it gets removed by the preprocessor
unless the project is configured with EFL_BETA_API_SUPPORT.  Moved the
@} outside the #ifdef so it will always be there and Doxygen won't
complain.

Test Plan: make doc 2> doxyerr.log

Reviewers: raster

Reviewed By: raster

CC: cedric

Differential Revision: https://phab.enlightenment.org/D609

src/lib/eo/Eo.h

@@ -1534,14 +1534,15 @@ EAPI extern const Eo_Event_Description _EO_EV_DEL;
  * @}
  */
 
+
+#endif
+
 /**
  * @}
  */
 
-#endif
-
 #ifdef __cplusplus
-}
+} 
 #endif
 
 #endif