dmaengine: sun6i: Add support for Allwinner A83T (sun8i) variant

The A83T SoC has the same dma engine as the A31 (sun6i), with a reduced
amount of endpoints and physical channels.

Signed-off-by: Jean-Francois Moine <[e-mail]>
Acked-by: Maxime Ripard <[e-mail]>
Signed-off-by: Vinod Koul <[e-mail]>

Documentation/devicetree/bindings/dma/sun6i-dma.txt

···
 - compatible:	Must be one of
 		  "allwinner,sun6i-a31-dma"
 		  "allwinner,sun8i-a23-dma"
+		  "allwinner,sun8i-a83t-dma"
 		  "allwinner,sun8i-h3-dma"
 - reg:		Should contain the registers base address and length
 - interrupts:	Should contain a reference to the interrupt used by this device

drivers/dma/sun6i-dma.c

···
 	.nr_max_vchans   = 37,
 };
 
+static struct sun6i_dma_config sun8i_a83t_dma_cfg = {
+	.nr_max_channels = 8,
+	.nr_max_requests = 28,
+	.nr_max_vchans   = 39,
+};
+
 /*
  * The H3 has 12 physical channels, a maximum DRQ port id of 27,
  * and a total of 34 usable source and destination endpoints.
···
 static const struct of_device_id sun6i_dma_match[] = {
 	{ .compatible = "allwinner,sun6i-a31-dma", .data = &sun6i_a31_dma_cfg },
 	{ .compatible = "allwinner,sun8i-a23-dma", .data = &sun8i_a23_dma_cfg },
+	{ .compatible = "allwinner,sun8i-a83t-dma", .data = &sun8i_a83t_dma_cfg },
 	{ .compatible = "allwinner,sun8i-h3-dma", .data = &sun8i_h3_dma_cfg },
 	{ /* sentinel */ }
 };