powerpc/mm: Remove very old comment in hash-4k.h

[Michael Ellerman]

On Tue, 2018-11-27 at 08:18:05 UTC, Michael Ellerman wrote:
> This comment talks about PTEs being 64-bits and PMD/PGD being 32-bits,
> but that hasn't been true since 2005 when David Gibson implemented
> 4-level page tables in the commit titled "Four level pagetables for
> ppc64".
> 
> Remove it.
> 
> Signed-off-by: Michael Ellerman <mpe at ellerman.id.au>

Applied to powerpc next.

https://git.kernel.org/powerpc/c/423e2f94456404b49d89ef587c3402

cheers