RFA: Fix per-thread watchpoint documentation

[Eli Zaretskii]

> From: Jim Blandy <jimb@codesourcery.com>
> Date: Mon, 17 Dec 2007 08:46:09 -0800
> 
> 
> The GDB documentation doesn't build at the moment, because the
> per-thread watchpoint documentation introduces an @item outside any
> @table.
> 
> One could fix this by simply wrapping a @table around the new @item,
> but it doesn't seem to me that that description is in the right place
> within its node.
> 
> So, does this look okay?

Yes, but you also changed other places which you didn't announce.  Not
that I object to them, though...

Thanks.