usb: renesas_usbhs: expand USB-DMAC channels for R-Car Gen2

This patch expands USB-DMAC channels for R-Car Gen2 SoCs. The SoCs
have 4 channels. If d{2,3}_{t,x}x_id are not set, this driver never
uses the expanded USB-DMAC channels.

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/include/linux/usb/renesas_usbhs.h b/include/linux/usb/renesas_usbhs.h
index d5952bb..9fd9e48 100644
--- a/include/linux/usb/renesas_usbhs.h
+++ b/include/linux/usb/renesas_usbhs.h
@@ -145,6 +145,10 @@
 	int d0_rx_id;
 	int d1_tx_id;
 	int d1_rx_id;
+	int d2_tx_id;
+	int d2_rx_id;
+	int d3_tx_id;
+	int d3_rx_id;
 
 	/*
 	 * option: