libnvdimm, testing: Add emulation for smart injection commands

Add support for the smart injection command in the nvdimm unit test
framework. This allows for directly injecting to smart fields and flags
that are supported in the injection command. If the injected values are
past the threshold, then an acpi notification is also triggered.

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>