make atomic_read() behave consistently on m32r

@@ -22,7 +22,7 @@
  * on us. We need to use _exactly_ the address the user gave us,
  * not some alias that contains the same information.
  */
-typedef struct { volatile int counter; } atomic_t;
+typedef struct { int counter; } atomic_t;
 
 #define ATOMIC_INIT(i)	{ (i) }
 

@@ -32,7 +32,7 @@ typedef struct { volatile int counter; }
  *
  * Atomically reads the value of @v.
  */
-#define atomic_read(v)	((v)->counter)
+#define atomic_read(v)	(*(volatile int *)&(v)->counter)
 
 /**
  * atomic_set - set atomic variable