Source file was removed.  Need to remove docbook reference also.
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Cc: Pavel Machek <pavel@suse.cz>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>