libnvdimm: fix SMART Health DSM payload definition

"NVDIMM DSM Interface Example" v1.2 made an incompatible change to the
layout of function1 "SMART and Health Info".  While the kernel does not
directly consume this payload, it does define it in ndctl.h that
userpace utilities consume.

Reported-by: Brian Boylston <brian.boylston@hpe.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>