[MIPS] Fix bug in atomic_sub_if_positive.

The branch optimization fixes in 2.6.21 introduced a bug in
atomic_sub_if_positive that causes it to return even when the sc
instruction fails. The result is that e.g. down_trylock becomes unreliable
as the semaphore counter is not always decremented.

Original MUA-shredded patch from Morten Larsen <mlarsen@broadcom.com>.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

include/asm-mips/atomic.h

@@ -283,10 +283,10 @@ static __inline__ int atomic_sub_if_positive(int i, atomic_t * v)
 		"	beqz	%0, 2f					\n"
 		"	 subu	%0, %1, %3				\n"
 		"	.set	reorder					\n"
-		"1:							\n"
 		"	.subsection 2					\n"
 		"2:	b	1b					\n"
 		"	.previous					\n"
+		"1:							\n"
 		"	.set	mips0					\n"
 		: "=&r" (result), "=&r" (temp), "=m" (v->counter)
 		: "Ir" (i), "m" (v->counter)
@@ -664,10 +664,10 @@ static __inline__ long atomic64_sub_if_positive(long i, atomic64_t * v)
 		"	beqz	%0, 2f					\n"
 		"	 dsubu	%0, %1, %3				\n"
 		"	.set	reorder					\n"
-		"1:							\n"
 		"	.subsection 2					\n"
 		"2:	b	1b					\n"
 		"	.previous					\n"
+		"1:							\n"
 		"	.set	mips0					\n"
 		: "=&r" (result), "=&r" (temp), "=m" (v->counter)
 		: "Ir" (i), "m" (v->counter)