usb: xhci: Add Renesas R-Car xHCI driver

Add firmware V3, firmware loader and XHCI glue for the Renesas R-Car
Gen3 SoCs XHCI controller. Thus far only the R-Car Gen3 R8A7795 ES2.0+
and R8A7796 are supported.

Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com>
Cc: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
Cc: Bin Meng <bmeng.cn@gmail.com>
diff --git a/drivers/usb/host/Makefile b/drivers/usb/host/Makefile
index 83903fc..79df888 100644
--- a/drivers/usb/host/Makefile
+++ b/drivers/usb/host/Makefile
@@ -59,6 +59,7 @@
 obj-$(CONFIG_USB_XHCI_MVEBU) += xhci-mvebu.o
 obj-$(CONFIG_USB_XHCI_OMAP) += xhci-omap.o
 obj-$(CONFIG_USB_XHCI_PCI) += xhci-pci.o
+obj-$(CONFIG_USB_XHCI_RCAR) += xhci-rcar.o
 obj-$(CONFIG_USB_XHCI_STI) += dwc3-sti-glue.o
 
 # designware