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/drivers/usb/dwc3/ep0.c b/drivers/usb/dwc3/ep0.c
index 818efb3..0c8c11d 100644
--- a/drivers/usb/dwc3/ep0.c
+++ b/drivers/usb/dwc3/ep0.c
@@ -13,6 +13,7 @@
  * commit c00552ebaf : Merge 3.18-rc7 into usb-next
  */
 #include <common.h>
+#include <cpu_func.h>
 #include <linux/kernel.h>
 #include <linux/list.h>