perf/arm-dsu: Assign parents for event_source device

Currently the PMU device appears directly under /sys/devices/
Only root busses should appear there, so instead assign the pmu->dev
parent to be the platform device.

Link: https://lore.kernel.org/linux-cxl/ZCLI9A40PJsyqAmq@kroah.com/
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20240412161057.14099-22-Jonathan.Cameron@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>

Author: jic23

drivers/perf/arm_dsu_pmu.c

@@ -742,6 +742,7 @@ static int dsu_pmu_device_probe(struct platform_device *pdev)
 
 	dsu_pmu->pmu = (struct pmu) {
 		.task_ctx_nr	= perf_invalid_context,
+		.parent		= &pdev->dev,
 		.module		= THIS_MODULE,
 		.pmu_enable	= dsu_pmu_enable,
 		.pmu_disable	= dsu_pmu_disable,