percpu, x86: Avoid warnings of unused variables in per cpu

Avoid hundreds of warnings with a gcc 4.6 -Wall build.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

arch/x86/include/asm/percpu.h

@@ -77,6 +77,7 @@ do {							\
 	if (0) {					\
 		pto_T__ pto_tmp__;			\
 		pto_tmp__ = (val);			\
+		(void)pto_tmp__;			\
 	}						\
 	switch (sizeof(var)) {				\
 	case 1:						\
@@ -115,6 +116,7 @@ do {									\
 	if (0) {							\
 		pao_T__ pao_tmp__;					\
 		pao_tmp__ = (val);					\
+		(void)pao_tmp__;					\
 	}								\
 	switch (sizeof(var)) {						\
 	case 1:								\