powerpc: implement clear_bit_unlock_is_negative_byte()

[Michael Ellerman]

On Tue, 2017-01-03 at 18:58:28 UTC, Nicholas Piggin wrote:
> Commit b91e1302ad9b8 ("mm: optimize PageWaiters bit use for
> unlock_page()") added a special bitop function to speed up
> unlock_page(). Implement this for powerpc.
...
> 
> Signed-off-by: Nicholas Piggin <npiggin at gmail.com>

Applied to powerpc next, thanks.

https://git.kernel.org/powerpc/c/d11914b21c4c21a294fe8937d66c1a

cheers