Use --nodes for setup-baremetal in toci_devtest

The old-style method for specifying nodes to setup-baremetal of passing
the JSON datafile along with --first or --not-first will be removed
soon. Switch the setup-baremetal call to the new-style of --nodes.

Change-Id: I0bfcbab455aeb5c386d3b548e255dad546fb6d44
Merge "Use --nodes for setup-baremetal in toci_devtest"