[PATCH, doc]: Fix "@anchor should not appear in @heading" warning

[Uros Bizjak]

On Sun, Sep 29, 2013 at 6:59 PM, Uros Bizjak <ubizjak@gmail.com> wrote:

> Rather trivial fix - put @anchor before @heading, as texi manual suggests.
>
> 2013-09-29  Uros Bizjak  <ubizjak@gmail.com>
>
>     * doc/install.texi (Host/target specific installation notes for GCC):
>     Put @anchor before @heading.
>
> Tested by "make doc" with texinfo 5.1 on Fedora 19.

I have committed both patches to mainline SVN under the assumption
that there were no objections.

Uros.