A cleanup `MDEV-19994 Add class Function_collection` (buildbot warnings)

plugin/versioning adds its own native functions by calling
item_create_append(). So GIS functions initialized two times.

Moving the initialization of GIS functions from item_create_append()
to item_create_init().

sql/item_create.cc

@@ -5764,7 +5764,15 @@ int item_create_init()
                    MYF(0)))
     DBUG_RETURN(1);
 
-  DBUG_RETURN(item_create_append(func_array));
+  if (item_create_append(func_array))
+    DBUG_RETURN(1);
+
+#ifdef HAVE_SPATIAL
+  if (function_collection_geometry.init())
+    DBUG_RETURN(1);
+#endif
+
+  DBUG_RETURN(0);
 }
 
 int item_create_append(Native_func_registry array[])
@@ -5788,11 +5796,6 @@ int item_create_append(Native_func_registry array[])
   }
 #endif
 
-#ifdef HAVE_SPATIAL
-  if (function_collection_geometry.init())
-    DBUG_RETURN(1);
-#endif
-
   DBUG_RETURN(0);
 }