The notification syndrome enum values are unused, remove them.

Link: https://lore.kernel.org/r/20210126120702.9807-6-galpress@amazon.comReviewed-by: NFiras JahJah <firasj@amazon.com>
Signed-off-by: NGal Pressman <galpress@amazon.com>
Signed-off-by: NJason Gunthorpe <jgg@nvidia.com>