[PATCH] atomic: add *_dec_not_zero

[David Howells]

Sven Eckelmann <sven at narfation.org> wrote:

> Introduce an *_dec_not_zero operation.  Make this a special case of
> *_add_unless because batman-adv uses atomic_dec_not_zero in different
> places like re-broadcast queue or aggregation queue management. There
> are other non-final patches which may also want to use this macro.
> 
> Reported-by: David S. Miller <davem at davemloft.net>
> Signed-off-by: Sven Eckelmann <sven at narfation.org>

Acked-by: David Howells <dhowells at redhat.com> [MN10300 and FRV]