coresight: trbe: Fix return value check in arm_trbe_register_coresight_cpu()

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

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Link: https://lore.kernel.org/r/20210409094901.1903622-1-weiyongjun1@huawei.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
diff --git a/drivers/hwtracing/coresight/coresight-trbe.c b/drivers/hwtracing/coresight/coresight-trbe.c
index 5ce2398..1768684 100644
--- a/drivers/hwtracing/coresight/coresight-trbe.c
+++ b/drivers/hwtracing/coresight/coresight-trbe.c
@@ -871,7 +871,7 @@ static void arm_trbe_register_coresight_cpu(struct trbe_drvdata *drvdata, int cp
 
 	dev = &cpudata->drvdata->pdev->dev;
 	desc.name = devm_kasprintf(dev, GFP_KERNEL, "trbe%d", cpu);
-	if (IS_ERR(desc.name))
+	if (!desc.name)
 		goto cpu_clear;
 
 	desc.type = CORESIGHT_DEV_TYPE_SINK;