usb: dwc3: fix the error returned with usb3_phy failure

When there is an error with the usb3_phy probe or absence, the error returned
is erroneously for usb2_phy.

Cc: <stable@vger.kernel.org>
Signed-off-by: Ruchika Kharwar <ruchika@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index c35d49d..358375e 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -450,7 +450,7 @@
 	}
 
 	if (IS_ERR(dwc->usb3_phy)) {
-		ret = PTR_ERR(dwc->usb2_phy);
+		ret = PTR_ERR(dwc->usb3_phy);
 
 		/*
 		 * if -ENXIO is returned, it means PHY layer wasn't