PM: Prototype the pm_generic_ operations

The pm_generic_ operations are all exported but are not prototyped in any
header file for direct use. Do so.

[rjw: Added extern.]
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

include/linux/pm.h

@@ -572,4 +572,11 @@ extern unsigned int	pm_flags;
 #define PM_APM	1
 #define PM_ACPI	2
 
+extern int pm_generic_suspend(struct device *dev);
+extern int pm_generic_resume(struct device *dev);
+extern int pm_generic_freeze(struct device *dev);
+extern int pm_generic_thaw(struct device *dev);
+extern int pm_generic_restore(struct device *dev);
+extern int pm_generic_poweroff(struct device *dev);
+
 #endif /* _LINUX_PM_H */