drm/amd/powerplay: Partially revert changes and fix smu7_notify_smc_display()

This partially reverts 0b6b4cbf77c995a34a4ec3d705a636434dadc51a and fixes
the noise issues on Tonga.

Signed-off-by: Tom St Denis <[e-mail]>
Reviewed-by: Alex Deucher <[e-mail]>
Acked-by: Harry Wentland <[e-mail]>
Signed-off-by: Alex Deucher <[e-mail]>

drivers/gpu/drm/amd/powerplay/hwmgr/smu7_hwmgr.c

···
 static int smu7_notify_smc_display(struct pp_hwmgr *hwmgr)
 {
 	struct smu7_hwmgr *data = (struct smu7_hwmgr *)(hwmgr->backend);
-	int ret = 0;
 
-	if (hwmgr->feature_mask & PP_VBI_TIME_SUPPORT_MASK) {
+	if (hwmgr->feature_mask & PP_VBI_TIME_SUPPORT_MASK)
 		smum_send_msg_to_smc_with_parameter(hwmgr,
 			(PPSMC_Msg)PPSMC_MSG_SetVBITimeout, data->frame_time_x2);
-		ret = (smum_send_msg_to_smc(hwmgr, (PPSMC_Msg)PPSMC_HasDisplay) == 0) ?  0 : -EINVAL;
-	}
-	return ret;
+	return (smum_send_msg_to_smc(hwmgr, (PPSMC_Msg)PPSMC_HasDisplay) == 0) ?  0 : -EINVAL;
 }
 
 static int smu7_set_power_state_tasks(struct pp_hwmgr *hwmgr, const void *input)