[x265] [PATCH 3 of 3] Make git X265_VERSION output the same as mercurial

[Ricardo Constantino]

On 14 June 2016 at 17:47, chen <chenm003 at 163.com> wrote:
>
> My Git 1.7.9 can't support "--first-parent", so the X265_LATEST_TAG will be
> empty, it made the cmake build failed.

That's already 4 years old.
The lack of --first-parent regarding LATEST_TAG can be fixed, but the
TAG_DISTANCE without it becomes too different from mercurial's. Dunno
what the devs prefer, empty tag distance or different from
mercurial's?