src: Rename source folders for atsam and atsamd architectures

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

src/atsam/usb_cdc_ep.h

@@ -0,0 +1,10 @@
+#ifndef __SAM3_USB_CDC_EP_H
+#define __SAM3_USB_CDC_EP_H
+
+enum {
+    USB_CDC_EP_ACM = 3,
+    USB_CDC_EP_BULK_OUT = 1,
+    USB_CDC_EP_BULK_IN = 2,
+};
+
+#endif // usb_cdc_ep.h