Hibernation: Mark SNAPSHOT_SET_SWAP_FILE ioctl as deprecated (rev. 2)

Mark the SNAPSHOT_SET_SWAP_FILE ioctl belonging to the hibernation userland
interface as deprecated.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Len Brown <len.brown@intel.com>