[Autotest] Fix unhandled AttributeError if machine_install failed

Part of the code was copied from autoupdater.py, should have replace
self.host.run with self.run.

BUG=chromium:222525
TEST=manually test in local machine

Change-Id: Ic5bac395b9a1a6d394cdebee32528cad5b63508b
Reviewed-on: https://gerrit.chromium.org/gerrit/46048
Tested-by: Dan Shi <dshi@chromium.org>
Reviewed-by: Richard Barnette <jrbarnette@chromium.org>
Commit-Queue: Dan Shi <dshi@chromium.org>
1 file changed