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/common/board_r.c b/common/board_r.c
index c0065a5..0764fcc 100644
--- a/common/board_r.c
+++ b/common/board_r.c
@@ -11,6 +11,7 @@
 
 #include <common.h>
 #include <api.h>
+#include <cpu_func.h>
 #include <u-boot/crc.h>
 /* TODO: can we just include all these headers whether needed or not? */
 #if defined(CONFIG_CMD_BEDBUG)