Now that we're entering the type-specific osload module era, it's
conceivable that modules might expose different parameters that users
could set (i.e., choose to reload via xmodem or tftp).  So, we allow users
to invoke os_load with a list of key/value pairs that get placed into the
reload_args hash argument to osload().

This will probably change later; it just preserves API compat for now.