When using "guix deploy" on an x86_64-linux machine to deploy a system to
i686-linux, DEPLOY-MANAGED-HOST would revert %CURRENT-SYSTEM to the host
system's value by the time it evaluated UPGRADE-SHEPHERD-SERVICES. The
earlier PARAMETERIZE would no longer be effective.
* gnu/machine/ssh.scm (deploy-managed-host): Ensure that
UPGRADE-SHEPHERD-SERVICES is evaluated for the architecture of the target
machine.
Change-Id: I0816da79cd7c46a69418717fa33b2fe4e2fabae0
9ce548a26e