[SPARC32]: Build fix.

Fix 6197fe4d720ea3e2ee94cdc7ef32d6c0151199de

arch/sparc/lib/atomic32.c: In function '__cmpxchg_u32':
arch/sparc/lib/atomic32.c:127: error: 'addr' undeclared (first use in this function)
arch/sparc/lib/atomic32.c:127: error: (Each undeclared identifier is reported only once
arch/sparc/lib/atomic32.c:127: error: for each function it appears in.)

I assume this is what was intended..

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: William Irwin <wli@holomorphy.com>
Signed-off-by: David S. Miller <davem@davemloft.net>