The Amaranth build system already supports remote builds over SSH.
This commit integrates it to the 'build' command.
* update dependencies
* add paramiko as a dependency (the SSH library used by amaranth)
* update dependencies.
* add amaranth-soc as a dependency, in order to reuse its bus
interfaces (e.g. Wishbone).
* add a `prog` argument to PowerFVSession that overrides the name of