common: Move ARM cache operations out of common.h

These functions are CPU-related and do not use driver model. Move them to
cpu_func.h

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/arch/arm/cpu/pxa/cache.c b/arch/arm/cpu/pxa/cache.c
index 5cd4a95..d4dfe7f 100644
--- a/arch/arm/cpu/pxa/cache.c
+++ b/arch/arm/cpu/pxa/cache.c
@@ -3,6 +3,7 @@
  * (C) Copyright 2016 Vasily Khoruzhick <anarsoul@gmail.com>
  */
 
+#include <cpu_func.h>
 #include <linux/types.h>
 #include <common.h>