Linux: autoconf.h is moving in 2.6.33

Linux: autoconf.h is moving in 2.6.33

In 2.6.33, <linux/autoconf.h> is moving to <generated/autoconf.h>.

Signed-off-by: Anders Kaseorg <andersk@mit.edu>
Change-Id: Ib97031728b89cf8e17581f3c425216ae4b5538ec
Reviewed-on: http://gerrit.openafs.org/1351
Reviewed-by: Marc Dionne <marc.c.dionne@gmail.com>
Tested-by: Marc Dionne <marc.c.dionne@gmail.com>
Reviewed-by: Derrick Brashear <shadow@dementia.org>
(cherry picked from commit 91e50aa81bdeecbdf351088b3b5510fe3c8e848e)
Reviewed-on: http://gerrit.openafs.org/1375
Tested-by: Derrick Brashear <shadow@dementia.org>