atomic.h: add atomic64 cmpxchg, xchg and add_unless to powerpc

[akpm@linux-foundation.org: build fixes]
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

include/asm-powerpc/atomic.h

@@ -165,8 +165,7 @@ static __inline__ int atomic_dec_return(atomic_t *v)
 	return t;
 }
 
-#define atomic_cmpxchg(v, o, n) \
-	((__typeof__((v)->counter))cmpxchg(&((v)->counter), (o), (n)))
+#define atomic_cmpxchg(v, o, n) (cmpxchg(&((v)->counter), (o), (n)))
 #define atomic_xchg(v, new) (xchg(&((v)->counter), new))
 
 /**
@@ -414,8 +413,7 @@ static __inline__ long atomic64_dec_if_positive(atomic64_t *v)
 	return t;
 }
 
-#define atomic64_cmpxchg(v, o, n) \
-	((__typeof__((v)->counter))cmpxchg(&((v)->counter), (o), (n)))
+#define atomic64_cmpxchg(v, o, n) (cmpxchg(&((v)->counter), (o), (n)))
 #define atomic64_xchg(v, new) (xchg(&((v)->counter), new))
 
 /**