drm/amdgpu: fix an error code in init_pmu_entry_by_type_and_add()

If the kmemdup() fails then this should return a negative error code
but it currently returns success

Fixes: b4a7db71 ("drm/amdgpu: add per device user friendly xgmi events for vega20")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu_pmu.c

@@ -519,8 +519,10 @@ static int init_pmu_entry_by_type_and_add(struct amdgpu_pmu_entry *pmu_entry,
 	pmu_entry->pmu.attr_groups = kmemdup(attr_groups, sizeof(attr_groups),
 								GFP_KERNEL);
 
-	if (!pmu_entry->pmu.attr_groups)
+	if (!pmu_entry->pmu.attr_groups) {
+		ret = -ENOMEM;
 		goto err_attr_group;
+	}
 
 	snprintf(pmu_name, PMU_NAME_SIZE, "%s_%d", pmu_entry->pmu_file_prefix,
 				adev_to_drm(pmu_entry->adev)->primary->index);