doc-guide: kernel-doc: fix example for inlined comments

Without ending with a ";", kernel-doc doesn't recognize it
as an struct, and it fails to parse the example.
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Documentation/doc-guide/kernel-doc.rst

@@ -237,7 +237,7 @@ on a line of their own, like all other kernel-doc comments::
         int baz;
         /** @foobar: Single line description. */
         int foobar;
-  }
+  };
 
 Nested structs/unions
 ~~~~~~~~~~~~~~~~~~~~~