[patch 04/28] Add cmpxchg64 and cmpxchg64_local to powerpc

[Paul Mackerras]

Mathieu Desnoyers writes:

> Make sure that at least cmpxchg64_local is available on all architectures to use
> for unsigned long long values.
> 
> Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers at polymtl.ca>

Acked-by: Paul Mackerras <paulus at samba.org>