PM / suspend: Use mem_sleep_labels[] strings in messages

Some messages in suspend.c currently print state names from
pm_states[], but that may be confusing if the mem_sleep sysfs
attribute is changed to anything different from "mem", because
in those cases the messages will say either "freeze" or "standby"
after writing "mem" to /sys/power/state.

To avoid the confusion, use mem_sleep_labels[] strings in those
messages instead.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c
index 5cf2327..a3d270e 100644
--- a/kernel/power/suspend.c
+++ b/kernel/power/suspend.c
@@ -560,7 +560,7 @@ static int enter_state(suspend_state_t state)
 	trace_suspend_resume(TPS("sync_filesystems"), 0, false);
 #endif
 
-	pm_pr_dbg("Preparing system for sleep (%s)\n", pm_states[state]);
+	pm_pr_dbg("Preparing system for sleep (%s)\n", mem_sleep_labels[state]);
 	pm_suspend_clear_flags();
 	error = suspend_prepare(state);
 	if (error)
@@ -570,7 +570,7 @@ static int enter_state(suspend_state_t state)
 		goto Finish;
 
 	trace_suspend_resume(TPS("suspend_enter"), state, false);
-	pm_pr_dbg("Suspending system (%s)\n", pm_states[state]);
+	pm_pr_dbg("Suspending system (%s)\n", mem_sleep_labels[state]);
 	pm_restrict_gfp_mask();
 	error = suspend_devices_and_enter(state);
 	pm_restore_gfp_mask();
@@ -597,7 +597,7 @@ int pm_suspend(suspend_state_t state)
 	if (state <= PM_SUSPEND_ON || state >= PM_SUSPEND_MAX)
 		return -EINVAL;
 
-	pr_info("PM: suspend entry (%s)\n", pm_states[state]);
+	pr_info("PM: suspend entry (%s)\n", mem_sleep_labels[state]);
 	error = enter_state(state);
 	if (error) {
 		suspend_stats.fail++;