Introduce CONFIG_SUSPEND for suspend-to-Ram and standby

Introduce CONFIG_SUSPEND representing the ability to enter system sleep
states, such as the ACPI S3 state, and allow the user to choose SUSPEND
and HIBERNATION independently of each other.

Make HOTPLUG_CPU be selected automatically if SUSPEND or HIBERNATION has
been chosen and the kernel is intended for SMP systems.

Also, introduce CONFIG_PM_SLEEP which is automatically selected if
CONFIG_SUSPEND or CONFIG_HIBERNATION is set and use it to select the
code needed for both suspend and hibernation.

The top-level power management headers and the ACPI code related to
suspend and hibernation are modified to use the new definitions (the
changes in drivers/acpi/sleep/main.c are, mostly, moving code to reduce
the number of ifdefs).

There are many other files in which CONFIG_PM can be replaced with
CONFIG_PM_SLEEP or even with CONFIG_SUSPEND, but they can be updated in
the future.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/suspend.h b/include/linux/suspend.h
index d16c1b8..388cace 100644
--- a/include/linux/suspend.h
+++ b/include/linux/suspend.h
@@ -24,7 +24,7 @@
 extern void drain_local_pages(void);
 extern void mark_free_pages(struct zone *zone);
 
-#if defined(CONFIG_PM) && defined(CONFIG_VT) && defined(CONFIG_VT_CONSOLE)
+#if defined(CONFIG_PM_SLEEP) && defined(CONFIG_VT) && defined(CONFIG_VT_CONSOLE)
 extern int pm_prepare_console(void);
 extern void pm_restore_console(void);
 #else
@@ -54,7 +54,6 @@
 	void (*restore_cleanup)(void);
 };
 
-#ifdef CONFIG_PM
 #ifdef CONFIG_HIBERNATION
 /* kernel/power/snapshot.c */
 extern void __register_nosave_region(unsigned long b, unsigned long e, int km);
@@ -82,6 +81,7 @@
 static inline int hibernate(void) { return -ENOSYS; }
 #endif /* CONFIG_HIBERNATION */
 
+#ifdef CONFIG_PM_SLEEP
 void save_processor_state(void);
 void restore_processor_state(void);
 struct saved_context;
@@ -106,7 +106,7 @@
 		{ .notifier_call = fn, .priority = pri };	\
 	register_pm_notifier(&fn##_nb);			\
 }
-#else /* CONFIG_PM */
+#else /* !CONFIG_PM_SLEEP */
 
 static inline int register_pm_notifier(struct notifier_block *nb)
 {
@@ -119,9 +119,9 @@
 }
 
 #define pm_notifier(fn, pri)	do { (void)(fn); } while (0)
-#endif /* CONFIG_PM */
+#endif /* !CONFIG_PM_SLEEP */
 
-#if !defined CONFIG_HIBERNATION || !defined(CONFIG_PM)
+#ifndef CONFIG_HIBERNATION
 static inline void register_nosave_region(unsigned long b, unsigned long e)
 {
 }