PCI: imx6: Return real error code from imx6_add_pcie_port()

When devm_request_irq() fails, imx6_add_pcie_port() should return the real
error code instead of always returning -ENODEV.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Bjorn Helgaas <helgaas@kernel.org>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
diff --git a/drivers/pci/host/pci-imx6.c b/drivers/pci/host/pci-imx6.c
index 8f3a981..2d0d0fe 100644
--- a/drivers/pci/host/pci-imx6.c
+++ b/drivers/pci/host/pci-imx6.c
@@ -539,7 +539,7 @@
 				       IRQF_SHARED, "mx6-pcie-msi", pp);
 		if (ret) {
 			dev_err(&pdev->dev, "failed to request MSI irq\n");
-			return -ENODEV;
+			return ret;
 		}
 	}