Description of problem:
HE deployment allows input of two MAC addresses at once for the engine.
   You may specify a unicast MAC address for the VM or accept a randomly generated default [00:16:3e:1e:39:6b]: 00:16:3E:7D:DD:DD00:16:3E:7D:DD:DD
          How should the engine VM network be configured (DHCP, Static)[DHCP]? 
          Add lines for the appliance itself and for this host to /etc/hosts on the engine VM?
          Note: ensuring that this host could resolve the engine VM hostname is still up to you
          (Yes, No)[No] yes
         

I've mistakenly provided the same MAC address twice for HE-VM and deployment procedure accepted that:

[ INFO  ] Stage: Setup validation
         
          --== CONFIGURATION PREVIEW ==--
         
          Bridge interface                   : enp4s0f0
          Engine FQDN                        : nsednev-he-4.scl.lab.tlv.redhat.com
          Bridge name                        : ovirtmgmt
          Host address                       : puma18.scl.lab.tlv.redhat.com
          SSH daemon port                    : 22
          Firewall manager                   : iptables
          Gateway address                    : 10.35.160.254
          Storage Domain type                : nfs3
          Image size GB                      : 50
          Host ID                            : 1
          Storage connection                 : 10.35.110.11:/Compute_NFS/nsednev_he_4
          Console type                       : vnc
          Memory size MB                     : 16384
          MAC address                        : 00:16:3E:7D:DD:DD00:16:3E:7D:DD:DD
          Number of CPUs                     : 6
          OVF archive (for disk boot)        : /usr/share/ovirt-engine-appliance/ovirt-engine-appliance-4.1-20161202.1.el7.centos.ova
          Appliance version                  : 4.1-20161202.1.el7.centos
          Restart engine VM after engine-setup: True
          Engine VM timezone                 : Asia/Jerusalem
          CPU Type                           : model_Westmere
         


Version-Release number of selected component (if applicable):
vdsm-4.18.999-1020.git1ff41b1.el7.centos.x86_64
libvirt-client-2.0.0-10.el7_3.2.x86_64
ovirt-vmconsole-1.0.4-1.el7ev.noarch
ovirt-release41-pre-4.1.0-0.0.beta.20161201085255.git731841c.el7.centos.noarch
sanlock-3.4.0-1.el7.x86_64
qemu-kvm-rhev-2.6.0-28.el7_3.2.x86_64
ovirt-hosted-engine-ha-2.1.0-0.0.master.20161130135331.20161130135328.git3541725.el7.centos.noarch
ovirt-engine-appliance-4.1-20161202.1.el7.centos.noarch
ovirt-host-deploy-1.6.0-0.0.master.20161107121647.gitfd7ddcd.el7.centos.noarch
ovirt-engine-sdk-python-3.6.9.1-1.el7ev.noarch
ovirt-imageio-common-0.5.0-0.201611201242.gitb02532b.el7.centos.noarch
ovirt-vmconsole-host-1.0.4-1.el7ev.noarch
mom-0.5.8-1.el7ev.noarch
ovirt-hosted-engine-setup-2.1.0-0.0.master.20161130101611.gitb3ad261.el7.centos.noarch
ovirt-setup-lib-1.1.0-0.0.master.20161107100014.gitb73abeb.el7.centos.noarch
ovirt-imageio-daemon-0.5.0-0.201611201242.gitb02532b.el7.centos.noarch
Linux version 3.10.0-514.2.2.el7.x86_64 (mockbuild.eng.bos.redhat.com) (gcc version 4.8.5 20150623 (Red Hat 4.8.5-11) (GCC) ) #1 SMP Wed Nov 16 13:15:13 EST 2016
Linux 3.10.0-514.2.2.el7.x86_64 #1 SMP Wed Nov 16 13:15:13 EST 2016 x86_64 x86_64 x86_64 GNU/Linux
Red Hat Enterprise Linux Server release 7.3 (Maipo)


How reproducible:
100%

Steps to Reproduce:
1.During deployment of HE, provide the same MAC address twice, and press enter to continue the deployment.
2.
3.

Actual results:
Deployment proceeds with double value of the same MAC.

Expected results:
Deployment should check for correct MAC address structure, at lest print an error and ask to provide correct MAC address, which should consist no more that of 6 octets.

Additional info: