[kernel] Make explicit that Normalize_only is the default mode.

src/kernel_services/cmdline_parameters/parameter_sig.mli

@@ -305,27 +305,27 @@ module type Specific_dir = sig
   (** @return whether the plugin <specific-dir> has been set. *)
 
   val get_dir:
-    ?mode:[`Create_path | `Normalize_only | `Must_exist ] ->
+    ?mode:[`Normalize_only | `Create_path |  `Must_exist ] ->
     string ->
     Filepath.Normalized.t
   (** [get_dir ?mode p] returns a local-path [p], relative to the plugin
       <specific-dir> directory, to a sub-directory of the plugin <specific-dir>
       directory.
       @param mode determines how to handle the resulting path:
+      + [Normalize_only] just normalizes the resulting path (default).
       + [Create_path] creates the resulting path, if does not exist.
-      + [Normalize_only] just normalizes the resulting path.
       + [Must_exist] aborts if the resulting path does not exist. *)
 
   val get_file:
-    ?mode:[`Create_path | `Normalize_only | `Must_exist ] ->
+    ?mode:[`Normalize_only | `Create_path |  `Must_exist ] ->
     string ->
     Filepath.Normalized.t
     (** [get_file ?mode p] returns a local-path [p], relative to the plugin
         <specific-dir> directory, to a file in the plugin <specific-dir>
         directory.
         @param mode determines how to handle the resulting path:
+        + [Normalize_only] just normalizes the resulting path (default).
         + [Create_path] creates the dirname of resulting path, if does not exist.
-        + [Normalize_only] just normalizes the resulting path.
         + [Must_exist] aborts if the resulting path does not exist. *)
 end