rcar_gen3: plat: Add R-Car V3M support

Add R-Car V3M support. This is based on the original
V3M support patch for Yocto v2.23.1 by Vladimir Barinov.

Signed-off-by: Vladimir Barinov <vladimir.barinov@cogentembedded.com>
Signed-off-by: Valentine Barshak <valentine.barshak@cogentembedded.com>
Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com>
---
Marek: Update on top of mainline ATF/master
diff --git a/drivers/renesas/rcar/dma/dma_driver.c b/drivers/renesas/rcar/dma/dma_driver.c
index fef55c4..e0be46e 100644
--- a/drivers/renesas/rcar/dma/dma_driver.c
+++ b/drivers/renesas/rcar/dma/dma_driver.c
@@ -16,7 +16,11 @@
 #include "rcar_private.h"
 
 /* DMA CHANNEL setting (0/16/32) */
+#if RCAR_LSI == RCAR_V3M
+#define	DMA_CH		16
+#else
 #define	DMA_CH		0
+#endif
 
 #if (DMA_CH == 0)
 #define SYS_DMAC_BIT	((uint32_t)1U << 19U)