libnvdimm, acpi, nfit: Add bus level dsm mask for pass thru.

Add a bus level dsm_mask to nvdimm_bus_descriptor to allow the passthru
calling mechanism to specify a different mask from the cmd_mask.

Populate bus_dsm_mask and use it to filter dsm calls that user can
make through the pass thru interface.

Signed-off-by: Jerry Hoemann <jerry.hoemann@hpe.com>
[djbw: use command number constants instead of a magic mask value]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>