docs-rst: kernel-doc: better output struct members

Right now, for a struct, kernel-doc produces the following output:

	.. c:type:: struct v4l2_prio_state

	   stores the priority states

	**Definition**

	::

	  struct v4l2_prio_state {
	    atomic_t prios[4];
	  };

	**Members**

	``atomic_t prios[4]``
	  array with elements to store the array priorities

Putting a member name in verbatim and adding a continuation line
causes the LaTeX output to generate something like:
	item[atomic_t prios\[4\]] array with elements to store the array priorities

Everything inside "item" is non-breakable, with may produce
lines bigger than the column width.

Also, for function members, like:

        int (* rx_read) (struct v4l2_subdev *sd, u8 *buf, size_t count,ssize_t *num);

It puts the name of the member at the end, like:

        int (*) (struct v4l2_subdev *sd, u8 *buf, size_t count,ssize_t *num) read

With is very confusing.

The best is to highlight what really matters: the member name.
is a secondary information.

So, change kernel-doc, for it to produce the output on a different way:

	**Members**

	``prios[4]``

	  array with elements to store the array priorities

Also, as the type is not part of LaTeX "item[]", LaTeX will split it into
multiple lines, if needed.

So, both LaTeX/PDF and HTML outputs will look good.

It should be noticed, however, that the way Sphinx LaTeX output handles
things like:

	Foo
	   bar

is different than the HTML output. On HTML, it will produce something
like:

	**Foo**
	   bar

While, on LaTeX, it puts both foo and bar at the same line, like:

	**Foo** bar

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