[PATCH] diff: clarify comparison as first parent

[Matt Mackall]

On Fri, 2015-12-18 at 13:06 -0600, timeless wrote:
> # HG changeset patch
> # User timeless <timeless at mozdev.org>
> # Date 1450464745 0
> #      Fri Dec 18 18:52:25 2015 +0000
> # Node ID 3bcfe6445cfe03119ac05bf57e00e50925826ce5
> # Parent  2916ebaef3129451bfd4f9f62487e70f74124d46
> diff: clarify comparison as first parent

Queued for default, thanks.

-- 
Mathematics is the supreme nostalgia of our time.