drm/amd/powerplay: Remove unneeded variable 'result' in vega10_hwmgr.c

Fixes coccicheck warning:

drivers/gpu/drm/amd/powerplay/hwmgr/vega10_hwmgr.c:4363:5-11: Unneeded variable: "result". Return "0" on line 4370
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/powerplay/hwmgr/vega10_hwmgr.c

@@ -4360,14 +4360,13 @@ static int vega10_set_watermarks_for_clocks_ranges(struct pp_hwmgr *hwmgr,
 	struct vega10_hwmgr *data = hwmgr->backend;
 	struct dm_pp_wm_sets_with_clock_ranges_soc15 *wm_with_clock_ranges = clock_range;
 	Watermarks_t *table = &(data->smc_state_table.water_marks_table);
-	int result = 0;
 
 	if (!data->registry_data.disable_water_mark) {
 		smu_set_watermarks_for_clocks_ranges(table, wm_with_clock_ranges);
 		data->water_marks_bitmap = WaterMarksExist;
 	}
 
-	return result;
+	return 0;
 }
 
 static int vega10_get_ppfeature_status(struct pp_hwmgr *hwmgr, char *buf)