Hi,

the "baud-rate" option for inputattach-service is broken, the
inputattach program expects the option to be named just "--baud".
The attached patch fixes the issue.

Just out of interest: Should we stick in Guix to the option used by the
program or stick with the old name?
I would like to keep the "baud-rate" name as it is the thing the
parameter configures: The baud-rate for the connection.

Tim.