One case of using __get_cpu_var in the get_cpu_var macro
for address calculation.

Signed-off-by: Christoph Lameter <cl@linux.com>

Index: linux/include/linux/percpu.h
===================================================================
--- linux.orig/include/linux/percpu.h	2013-12-02 16:07:46.904713849 -0600
+++ linux/include/linux/percpu.h	2013-12-02 16:09:23.000000000 -0600
@@ -28,7 +28,7 @@
  */
 #define get_cpu_var(var) (*({				\
 	preempt_disable();				\
-	&__get_cpu_var(var); }))
+	this_cpu_ptr(&var); }))
 
 /*
  * The weird & is necessary because sparse considers (void)(var) to be