NVMe: Define SMART log

This data structure is defined in the NVMe specification.  It's not used
by the kernel, but is available for use by userspace software.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
diff --git a/drivers/block/nvme.c b/drivers/block/nvme.c
index c1d5444..270805c 100644
--- a/drivers/block/nvme.c
+++ b/drivers/block/nvme.c
@@ -135,6 +135,7 @@
 	BUILD_BUG_ON(sizeof(struct nvme_id_ctrl) != 4096);
 	BUILD_BUG_ON(sizeof(struct nvme_id_ns) != 4096);
 	BUILD_BUG_ON(sizeof(struct nvme_lba_range_type) != 64);
+	BUILD_BUG_ON(sizeof(struct nvme_smart_log) != 512);
 }
 
 typedef void (*nvme_completion_fn)(struct nvme_dev *, void *,