PCI: qcom: Prevent potential error pointer dereference

Only call dev_pm_opp_put() if dev_pm_opp_find_freq_exact() succeeds;
otherwise it leads to an error pointer dereference.

Fixes: 78b5f6f ("PCI: qcom: Add OPP support to scale performance")
Link: https://lore.kernel.org/linux-pci/[email protected]
Signed-off-by: Dan Carpenter <[email protected]>
Signed-off-by: Krzysztof Wilczyński <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Tested-by: Anders Roxell <[email protected]>
Reviewed-by: Manivannan Sadhasivam <[email protected]>

Author: Dan Carpenter

drivers/pci/controller/dwc/pcie-qcom.c

@@ -1447,8 +1447,8 @@ static void qcom_pcie_icc_opp_update(struct qcom_pcie *pcie)
 			if (ret)
 				dev_err(pci->dev, "Failed to set OPP for freq (%lu): %d\n",
 					freq_kbps * width, ret);
+			dev_pm_opp_put(opp);
 		}
-		dev_pm_opp_put(opp);
 	}
 }