Suspend: Clean up suspend_64.c

There's a freakishly long comment in suspend_64.c, shorten it.

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