perf: remove duplicate check on fwnode

fwnode is checked IS_ERR_OR_NULL in following check by
is_of_node() or is_acpi_device_node(), remove duplicate check.
Signed-off-by: Wang Qing <wangqing@vivo.com>
Link: https://lore.kernel.org/r/1604644902-29655-1-git-send-email-wangqing@vivo.comSigned-off-by: Will Deacon <will@kernel.org>

drivers/perf/arm_dsu_pmu.c

@@ -716,9 +716,6 @@ static int dsu_pmu_device_probe(struct platform_device *pdev)
 	if (IS_ERR(dsu_pmu))
 		return PTR_ERR(dsu_pmu);
 
-	if (IS_ERR_OR_NULL(fwnode))
-		return -ENOENT;
-
 	if (is_of_node(fwnode))
 		rc = dsu_pmu_dt_get_cpus(&pdev->dev, &dsu_pmu->associated_cpus);
 	else if (is_acpi_device_node(fwnode))