PM / timekeeping: Print debug messages when requested

The messages printed by tk_debug_account_sleep_time() are basically
useful for system sleep debugging, so print them only when the other
debug messages from the core suspend/hibernate code are enabled.

While at it, make it clear that the messages from
tk_debug_account_sleep_time() are about timekeeping suspend
duration, because in general timekeeping may be suspeded and
resumed for multiple times during one system suspend-resume cycle.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/include/linux/suspend.h b/include/linux/suspend.h
index 707e4cd..97e394f 100644
--- a/include/linux/suspend.h
+++ b/include/linux/suspend.h
@@ -492,16 +492,22 @@ static inline void unlock_system_sleep(void) {}
 
 #ifdef CONFIG_PM_SLEEP_DEBUG
 extern bool pm_print_times_enabled;
-extern __printf(1, 2) void pm_pr_dbg(const char *fmt, ...);
+extern __printf(2, 3) void __pm_pr_dbg(bool defer, const char *fmt, ...);
 #else
 #define pm_print_times_enabled	(false)
 
 #include <linux/printk.h>
 
-#define pm_pr_dbg(fmt, ...) \
+#define __pm_pr_dbg(defer, fmt, ...) \
 	no_printk(KERN_DEBUG fmt, ##__VA_ARGS__)
 #endif
 
+#define pm_pr_dbg(fmt, ...) \
+	__pm_pr_dbg(false, fmt, ##__VA_ARGS__)
+
+#define pm_deferred_pr_dbg(fmt, ...) \
+	__pm_pr_dbg(true, fmt, ##__VA_ARGS__)
+
 #ifdef CONFIG_PM_AUTOSLEEP
 
 /* kernel/power/autosleep.c */