ecore_drm: fix Doxygen markup to prevent warnings.

Summary:
These files are missing group titles on the @defgroup line.  Added the titles so Doxygen does not
complain.

Test Plan: make doc 2> doc/doxyerr.log

CC: cedric

Differential Revision: https://phab.enlightenment.org/D612

Signed-off-by: Cedric BAIL <cedric.bail@free.fr>

src/lib/ecore_drm/ecore_drm_fb.c

@@ -5,7 +5,10 @@
 #include "ecore_drm_private.h"
 
 /**
- * @defgroup Ecore_Drm_Fb_Group
+ * @defgroup Ecore_Drm_Fb_Group Frame buffer manipulation
+ * 
+ * Functions that deal with frame buffers.
+ * 
  * 
  */
 

src/lib/ecore_drm/ecore_drm_output.c

@@ -440,7 +440,9 @@ finish:
 }
 
 /**
- * @defgroup Ecore_Drm_Output_Group
+ * @defgroup Ecore_Drm_Output_Group Ecore DRM Output
+ * 
+ * Functions to manage DRM outputs.
  * 
  */
 

src/lib/ecore_drm/ecore_drm_sprites.c

@@ -5,7 +5,9 @@
 #include "ecore_drm_private.h"
 
 /**
- * @defgroup Ecore_Drm_Sprite_Group
+ * @defgroup Ecore_Drm_Sprites_Group Ecore DRM Sprites
+ * 
+ * Functions for managing DRM sprites.
  * 
  */