[PATCH, doc]: Rename Index node to prevent file collision

[Eli Zaretskii]

> From: Michael Hope <michael.hope@linaro.org>
> Date: Mon, 2 Jul 2012 13:02:56 +1200
> Cc: brobecker@adacore.com, joseph@codesourcery.com, gdb-patches@sourceware.org
> 
> On 2 July 2012 07:55, Eli Zaretskii <eliz@gnu.org> wrote:
> > Ping!  Should I commit this?
> 
> It fixes my issue,

Committed.