acpi, nfit: allow override of built-in bitmasks for nvdimm DSMs

acpi, nfit: allow override of built-in bitmasks for nvdimm DSMs

As it is today, we can't enable or test new NVDIMM management functions
provided by new firmware and tools without changing the kernel.  We also
can't prevent documented DSM functions from being called in the case of
buggy firmware.  This patch provides a module parameter that overrides
the DSM function mask that is built into the kernel.

If the "disable_vendor_specific" module parameter is also used we ignore
the new parameter.

Signed-off-by: Linda Knippers <linda.knippers@hpe.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>