Almost unused functions in mountmgr.sys

[Francois Gouget]

So I have a script telling me that, in mountmgr.sys, create_scsi_entry() 
and set_scsi_device_name() are not used.

Looking into this it turns out that they are only used on macOS and on 
Linux distributions that still have libhal, which I expect most 
distributions have dropped in favor of libdbus-1.

So are we missing code to use these on modern Linux machines that have 
libdbus-1 but not libhal? Or is there something else at play?