eo: Mark name_find as const

The search should not require a mutable object.
See the previous commit on elm_widget.

src/lib/eo/efl_object.eo

@@ -164,7 +164,7 @@ abstract Efl.Object ()
          [[Called at the end of #eo_add. Should not be called, just overridden.]]
          return: Efl.Object; [[The new object created, can be NULL if aborting]]
       }
-      name_find {
+      name_find @const {
          [[Find a child object with the given name and return it.
 
            The search string can be a glob (shell style, using *). It can also

src/lib/eo/eo_base_class.c

@@ -448,7 +448,7 @@ _ismultiglob(const char *match)
 }
 
 EOLIAN static Efl_Object *
-_efl_object_name_find(Eo *obj EINA_UNUSED, Efl_Object_Data *pd, const char *search)
+_efl_object_name_find(const Eo *obj EINA_UNUSED, Efl_Object_Data *pd, const char *search)
 {
    Eo *child;
    _Eo_Object *child_eo;