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: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
1 file changed