usb: fix building musb drivers

Commit 3dacdf11 "usb: factor out state_string() on otg drivers"
broke building musb drivers since there is already another
otg_state_string() function in musb drivers, but with different
prototype. Fix musb drivers to use common otg_state_string(), too.

Also provide a nop for otg_state_string() if CONFIG_USB_OTG_UTILS
is not defined.

Signed-off-by: Anatolij Gustschin <agust@denx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/musb/musb_virthub.c b/drivers/usb/musb/musb_virthub.c
index 489104a..bb1247d 100644
--- a/drivers/usb/musb/musb_virthub.c
+++ b/drivers/usb/musb/musb_virthub.c
@@ -98,7 +98,7 @@
 #endif
 		default:
 			DBG(1, "bogus rh suspend? %s\n",
-				otg_state_string(musb));
+				otg_state_string(musb->xceiv->state));
 		}
 	} else if (power & MUSB_POWER_SUSPENDM) {
 		power &= ~MUSB_POWER_SUSPENDM;
@@ -208,7 +208,8 @@
 		musb->xceiv->state = OTG_STATE_B_IDLE;
 		break;
 	default:
-		DBG(1, "host disconnect (%s)\n", otg_state_string(musb));
+		DBG(1, "host disconnect (%s)\n",
+			otg_state_string(musb->xceiv->state));
 	}
 }