PM: Remove saved_state from struct dev_pm_info

The saved_state member of struct dev_pm_info, defined in include/linux/pm.h, is
not used anywhere, so it can be removed.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>