usb: musb: am35x: fix error return code in am35x_probe()

Fix to return a negative error code from the usb_phy_generic_register()
error handling case instead of 0, as done elsewhere in this function.

Signed-off-by: Wei Yongjun <[e-mail]>
Signed-off-by: Bin Liu <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/usb/musb/am35x.c

···
 	pdata->platform_ops		= &am35x_ops;
 
 	glue->phy = usb_phy_generic_register();
-	if (IS_ERR(glue->phy))
+	if (IS_ERR(glue->phy)) {
+		ret = PTR_ERR(glue->phy);
 		goto err7;
+	}
 	platform_set_drvdata(pdev, glue);
 
 	pinfo = am35x_dev_info;