usb: musb: move function declarations to musb_{host,gadget}.h

Let the function declarations live in the header files they belong to,
which makes it easier to stub them out later.

Signed-off-by: Daniel Mack <zonque@gmail.com>
Acked-by: Peter Korsgaard <jacmet@sunsite.dk>
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/musb/musb_host.h

@@ -84,7 +84,9 @@ static inline struct musb_qh *first_qh(struct list_head *q)
 	return list_entry(q->next, struct musb_qh, ring);
 }
 
-
+extern irqreturn_t musb_h_ep0_irq(struct musb *);
+extern void musb_host_tx(struct musb *, u8);
+extern void musb_host_rx(struct musb *, u8);
 extern void musb_root_disconnect(struct musb *musb);
 
 struct usb_hcd;