tools/testing/nvdimm: test acpi 6.1 health state flags

Add a simulated dimm with an ACPI_NFIT_MEM_MAP_FAILED indication, and
set the ACPI_NFIT_MEM_HEALTH_ENABLED flag on all the dimms where
nfit_test simulates health events, but spread it out over several
redundant memdev entries to test that the nfit driver coalesces all the
flags.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>