ARC: Implement a function to sync and cleanup caches

Implement specialized function to clenup caches (and therefore
sync instruction and data caches) which can be used for cleanup before linux
launch or to sync caches during U-Boot self-relocation.

Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>

arch/arc/lib/init_helpers.c

@@ -4,14 +4,14 @@
  * SPDX-License-Identifier:	GPL-2.0+
  */
 
+#include <asm/cache.h>
 #include <common.h>
 
 DECLARE_GLOBAL_DATA_PTR;
 
 int init_cache_f_r(void)
 {
-#ifndef CONFIG_SYS_DCACHE_OFF
-	flush_dcache_all();
-#endif
+	sync_n_cleanup_cache_all();
+
 	return 0;
 }