libnvdimm, btt: BTT updates for UEFI 2.7 format

The UEFI 2.7 specification defines an updated BTT metadata format,
bumping the revision to 2.0. Add support for the new format, while
retaining compatibility for the old 1.1 format.

Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Linda Knippers <linda.knippers@hpe.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
diff --git a/drivers/nvdimm/nd.h b/drivers/nvdimm/nd.h
index e802c87..e1b5715 100644
--- a/drivers/nvdimm/nd.h
+++ b/drivers/nvdimm/nd.h
@@ -195,6 +195,9 @@ struct nd_btt {
 	u64 size;
 	u8 *uuid;
 	int id;
+	int initial_offset;
+	u16 version_major;
+	u16 version_minor;
 };
 
 enum nd_pfn_mode {