usb: dwc3: move gadget prototypes to core.h

host prototypes are there, let's move gadget's
closer.

Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index a775543..513a739 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -791,4 +791,7 @@
 int dwc3_host_init(struct dwc3 *dwc);
 void dwc3_host_exit(struct dwc3 *dwc);
 
+int dwc3_gadget_init(struct dwc3 *dwc);
+void dwc3_gadget_exit(struct dwc3 *dwc);
+
 #endif /* __DRIVERS_USB_DWC3_CORE_H */