As found on some arm defconfigs.

I only looked at how original patch changes things and other patches fix
compilation. ;-)
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>