usb: gadget: renesas_usbhs: fixup driver compile style

In current renesas-usbhs,
there was inconsistency about the style of kernel module or built-in.
This patch solve it.

[ balbi@ti.com : fix compile issue when building modules ]

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/renesas_usbhs/Kconfig b/drivers/usb/renesas_usbhs/Kconfig
index 286cbf1..97a4401 100644
--- a/drivers/usb/renesas_usbhs/Kconfig
+++ b/drivers/usb/renesas_usbhs/Kconfig
@@ -5,6 +5,7 @@
 config USB_RENESAS_USBHS
 	tristate 'Renesas USBHS controller'
 	depends on SUPERH || ARCH_SHMOBILE
+	depends on USB && USB_GADGET
 	default n
 	help
 	  Renesas USBHS is a discrete USB host and peripheral controller chip