usb: dwc3: move dwc3 device ID bitmap to core.c

if we want to support situations where we have
both SoC and PCIe versions of the IP on the same
platform, we need to have sequential numbers between
them, otherwise we will still have name collisions.

Because of that, we need to move dwc3_get/put_device_id()
to core.c and export that symbol to be used by glue
layers.

Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index bebb5e1..95d5a87b 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -793,4 +793,7 @@
 int dwc3_gadget_init(struct dwc3 *dwc);
 void dwc3_gadget_exit(struct dwc3 *dwc);
 
+extern int dwc3_get_device_id(void);
+extern void dwc3_put_device_id(int id);
+
 #endif /* __DRIVERS_USB_DWC3_CORE_H */