staging: mt7621-pci: avoid use 'err' local variable

Function 'mt7621_pcie_request_resources' is using 'err'
local variable to get value returned from 'devm_request_pci_bus_resources'
and returning after that. This is not needed at all. Instead of that
just directly return returned value by the function which is also
returning zero on success.
Signed-off-by: Sergio Paracuellos <sergio.paracuellos@gmail.com>
Link: https://lore.kernel.org/r/20190720072908.16795-1-sergio.paracuellos@gmail.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/mt7621-pci/pci-mt7621.c

@@ -617,17 +617,12 @@ static int mt7621_pcie_request_resources(struct mt7621_pcie *pcie,
 					 struct list_head *res)
 {
 	struct device *dev = pcie->dev;
-	int err;
 
 	pci_add_resource_offset(res, &pcie->io, pcie->offset.io);
 	pci_add_resource_offset(res, &pcie->mem, pcie->offset.mem);
 	pci_add_resource(res, &pcie->busn);
 
-	err = devm_request_pci_bus_resources(dev, res);
-	if (err < 0)
-		return err;
-
-	return 0;
+	return devm_request_pci_bus_resources(dev, res);
 }
 
 static int mt7621_pcie_register_host(struct pci_host_bridge *host,