rcar_gen3: drivers: ddr_a: Add D3 DDR init

Add R-Car D3 DDR initialization code. The code is in staging and needs
cleanup, and possibly can even be merged with the E3 init code.

Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com>
diff --git a/drivers/staging/renesas/rcar/ddr/ddr.mk b/drivers/staging/renesas/rcar/ddr/ddr.mk
index ef13413..a73d227 100644
--- a/drivers/staging/renesas/rcar/ddr/ddr.mk
+++ b/drivers/staging/renesas/rcar/ddr/ddr.mk
@@ -6,8 +6,10 @@
 
 ifeq (${RCAR_LSI},${RCAR_E3})
     include drivers/staging/renesas/rcar/ddr/ddr_a/ddr_a.mk
+    BL2_SOURCES += drivers/staging/renesas/rcar/ddr/dram_sub_func.c
+else ifeq (${RCAR_LSI},${RCAR_D3})
+    include drivers/staging/renesas/rcar/ddr/ddr_a/ddr_a.mk
 else
     include drivers/staging/renesas/rcar/ddr/ddr_b/ddr_b.mk
+    BL2_SOURCES += drivers/staging/renesas/rcar/ddr/dram_sub_func.c
 endif
-
-BL2_SOURCES += drivers/staging/renesas/rcar/ddr/dram_sub_func.c