[Baremetal] Modify interaction with bifrost roles

[Baremetal] Modify interaction with bifrost roles

Change some of the variables when calling opnfv-virtual.yml and
baremetal=true:

1 - We want to configure DHCP mapping between ip and mac when doing
baremetal. The create-nodes role will generate a file with that
mapping for us (baremetalstaticips)

2 - Don't download the standard IPA image but build one with Fedora
(only one that works in ericsson-pod2) when doing baremetal

3 - Wait for the blade to complete its booting. Its ssh port becomes
available with the IPA provision but that is not the final state.
We need to wait until the required distro gets installed.
When not doing baremetal, this is fine as the VMs boot very fast with
the chosen distro but for baremetal it takes a while (ericsson-pod2
servers take around 2 minutes to finish all BIOS booting). The playbook
wait-for-baremetal.yml does this.

Change-Id: I5536517209ff7f46ec034554d29566707778e397
Signed-off-by: Manuel Buil <mbuil@suse.com>