coresight: tnoc: Fix a NULL vs IS_ERR() bug in probe

The devm_ioremap_resource() function returns error pointers on error.
It never returns NULL.  Update the error checking to match.

Fixes: e54a52a ("coresight: add coresight Trace Network On Chip driver")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/7bd9fae8-a15f-412a-8800-ce47acf0b5ce@sabinyo.mountain

Author: Dan Carpenter

drivers/hwtracing/coresight/coresight-tnoc.c

@@ -183,8 +183,8 @@ static int trace_noc_probe(struct amba_device *adev, const struct amba_id *id)
 	dev_set_drvdata(dev, drvdata);
 
 	drvdata->base = devm_ioremap_resource(dev, &adev->res);
-	if (!drvdata->base)
-		return -ENOMEM;
+	if (IS_ERR(drvdata->base))
+		return PTR_ERR(drvdata->base);
 
 	spin_lock_init(&drvdata->spinlock);