thermal: core: fix some format issues on critical shutdown string

The critical shutdown notice string used to have some spaces missing,
which makes it not so pretty.

Add the spaces to satisfy usual English space rules.
Reported-by: NMingcong Bai <jeffbai@aosc.io>
Signed-off-by: NIcenowy Zheng <icenowy@aosc.io>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

drivers/thermal/thermal_core.c

@@ -390,7 +390,7 @@ static void handle_critical_trips(struct thermal_zone_device *tz,
 
 	if (trip_type == THERMAL_TRIP_CRITICAL) {
 		dev_emerg(&tz->device,
-			  "critical temperature reached(%d C),shutting down\n",
+			  "critical temperature reached (%d C), shutting down\n",
 			  tz->temperature / 1000);
 		mutex_lock(&poweroff_lock);
 		if (!power_off_triggered) {