docs: kernel-doc.rst: improve private members description

The private members section can now be moved to be together
with the arguments section. Move it there and add an example
about the usage of public:
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: NJonathan Corbet <corbet@lwn.net>

Documentation/doc-guide/kernel-doc.rst

@@ -167,6 +167,36 @@ notation as::
 
       * @...: description
 
+Private members
+~~~~~~~~~~~~~~~
+
+Inside a struct or union description, you can use the ``private:`` and
+``public:`` comment tags. Structure fields that are inside a ``private:``
+area are not listed in the generated output documentation.
+
+The ``private:`` and ``public:`` tags must begin immediately following a
+``/*`` comment marker.  They may optionally include comments between the
+``:`` and the ending ``*/`` marker.
+
+Example::
+
+  /**
+   * struct my_struct - short description
+   * @a: first member
+   * @b: second member
+   * @d: fourth member
+   *
+   * Longer description
+   */
+  struct my_struct {
+      int a;
+      int b;
+  /* private: internal use only */
+      int c;
+  /* public: the next one is public */
+      int d;
+  };
+
 
 Highlights and cross-references
 -------------------------------
@@ -332,32 +362,6 @@ on a line of their own, like all other kernel-doc comments::
         int foobar;
   }
 
-Private members
-~~~~~~~~~~~~~~~
-
-Inside a struct description, you can use the "private:" and "public:" comment
-tags. Structure fields that are inside a "private:" area are not listed in the
-generated output documentation.  The "private:" and "public:" tags must begin
-immediately following a ``/*`` comment marker.  They may optionally include
-comments between the ``:`` and the ending ``*/`` marker.
-
-Example::
-
-  /**
-   * struct my_struct - short description
-   * @a: first member
-   * @b: second member
-   *
-   * Longer description
-   */
-  struct my_struct {
-      int a;
-      int b;
-  /* private: internal use only */
-      int c;
-  };
-
-
 Typedef documentation
 ---------------------