Attempt to request an optional device-specific DDP package file
(one with the PCIe Device Serial Number in its name so that different DDP
package files can be used on different devices). If the optional package
file exists, download it to the device. If not, download the default
package file.

Log an appropriate message based on whether or not a DDP package
file exists and the return code from the attempt to download it to the
device.  If the download fails and there is not already a package file on
the device, go into "Safe Mode" where some features are not supported.
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>