snowball: arm cpu: inv and clean of L2

TODO: make this patch board specific. E.g add a board hook
      in cpu.c that the board may implement.
      Use generic cache functions for clean and inv, not hardcoded registers.
diff --git a/arch/arm/cpu/armv7/cpu.c b/arch/arm/cpu/armv7/cpu.c
index 662c496..c0f2b6f 100644
--- a/arch/arm/cpu/armv7/cpu.c
+++ b/arch/arm/cpu/armv7/cpu.c
@@ -78,6 +78,13 @@
 	 * problems for kernel
 	 */
 	invalidate_dcache_all();
-
+#ifdef CONFIG_U8500
+	/* Clean l2 */
+	*((volatile unsigned int *)(0xA04127BC)) = 0xFF;
+	while (*((volatile unsigned int *)(0xA04127BC)) & 0xFF);
+	/* Invalidate l2 */
+	*((volatile unsigned int *)(0xA041277C)) = 0xFF;
+	while (*((volatile unsigned int *)(0xA041277C)) & 0xFF);
+#endif
 	return 0;
 }