usb: dwc3: pci: fix another failure path in dwc3_pci_probe()

When applying commit 7d26b58 (fix failure path in
dwc3_pci_probe()), I mistakenly left out one of the
possible failures where we would return success even
on the error case.

This patch fixes that mistake.

Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/usb/dwc3/dwc3-pci.c b/drivers/usb/dwc3/dwc3-pci.c
index dcc6479..20d0c8a 100644
--- a/drivers/usb/dwc3/dwc3-pci.c
+++ b/drivers/usb/dwc3/dwc3-pci.c
@@ -89,6 +89,7 @@
 	dwc3 = platform_device_alloc("dwc3", devid);
 	if (!dwc3) {
 		dev_err(dev, "couldn't allocate dwc3 device\n");
+		ret = -ENOMEM;
 		goto err1;
 	}