Automatically set the comment style to what we use

[Eli Zaretskii]

> From: Yao Qi <qiyaoltc@gmail.com>
> Date: Thu, 22 Jun 2017 16:14:04 +0100
> Cc: "gdb-patches@sourceware.org" <gdb-patches@sourceware.org>
> 
> On Thu, Jun 22, 2017 at 4:04 PM, Eli Zaretskii <eliz@gnu.org> wrote:
> > And btw, what about the patch I suggested?  Is it OK to push it?
> 
> Yes, please.

Thanks, pushed to master.