clk: qcom: Fix return value check in apss_ipq6018_probe()

In case of error, the function dev_get_regmap() returns NULL pointer
not ERR_PTR(). The IS_ERR() test in the return value check should be
replaced with NULL test.

Fixes: 5e77b4ef1b19 ("clk: qcom: Add ipq6018 apss clock controller")
Reported-by: Hulk Robot <[e-mail]>
Signed-off-by: Wei Yongjun <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Stephen Boyd <[e-mail]>

drivers/clk/qcom/apss-ipq6018.c

···
 	struct regmap *regmap;
 
 	regmap = dev_get_regmap(pdev->dev.parent, NULL);
-	if (IS_ERR(regmap))
-		return PTR_ERR(regmap);
+	if (!regmap)
+		return -ENODEV;
 
 	return qcom_cc_really_probe(pdev, &apss_ipq6018_desc, regmap);
 }