src: Rename source folders for atsam and atsamd architectures

Signed-off-by: Florian Heilmann <Florian.Heilmann@gmx.net>

src/atsam/sam4_cache.c

@@ -0,0 +1,16 @@
+// SAM4 cache enable
+//
+// Copyright (C) 2018  Kevin O'Connor <kevin@koconnor.net>
+//
+// This file may be distributed under the terms of the GNU GPLv3 license.
+
+#include "sam4e.h" // CMCC
+#include "sched.h" // DECL_INIT
+
+void
+sam4_cache_init(void)
+{
+    if (!(CMCC->CMCC_SR & CMCC_SR_CSTS))
+        CMCC->CMCC_CTRL = CMCC_CTRL_CEN;
+}
+DECL_INIT(sam4_cache_init);