phy: qcom-qusb2: fix missing assignment of ret when calling clk_prepare_enable

The error return from the call to clk_prepare_enable is not being assigned
to variable ret even though ret is being used to check if the call failed.
Fix this by adding in the missing assignment.

Addresses-Coverity: ("Logically dead code")
Fixes: 891a96f65a ("phy: qcom-qusb2: Add support for runtime PM")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>

drivers/phy/qualcomm/phy-qcom-qusb2.c

@@ -564,7 +564,7 @@ static int __maybe_unused qusb2_phy_runtime_resume(struct device *dev)
 	}
 
 	if (!qphy->has_se_clk_scheme) {
-		clk_prepare_enable(qphy->ref_clk);
+		ret = clk_prepare_enable(qphy->ref_clk);
 		if (ret) {
 			dev_err(dev, "failed to enable ref clk, %d\n", ret);
 			goto disable_ahb_clk;