rcar_gen3: plat: Add initial D3 support

Add R-Car D3 SoC platform specifics. Driver, PFC, QoS, DDR init code
will be added separately.

Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com>
diff --git a/tools/renesas/rcar_layout_create/sa0.c b/tools/renesas/rcar_layout_create/sa0.c
index b902d33..79354ec 100644
--- a/tools/renesas/rcar_layout_create/sa0.c
+++ b/tools/renesas/rcar_layout_create/sa0.c
@@ -4,7 +4,7 @@
  * SPDX-License-Identifier: BSD-3-Clause
  */
 
-#define RCAR_SA0_SIZE_SMALL	(0)	/* for E3 */
+#define RCAR_SA0_SIZE_SMALL	(0)	/* for E3/D3 */
 #define RCAR_SA0_SIZE_NORMAL	(1)	/* for H3/M3/M3N */
 
 #define BL2_ADDRESS	(0xE6304000)	/* BL2 start address */