Install seabios-bin on rhel7
Install seabios-bin on rhel7

Without the files in the seabios-bin package Nova instances on rhel7
fail to start with an error about missing rom files.

Change-Id: I50b28e7a3564819d22e20854fd28d2fca48c0245

radez/tripleo-image-elements,radez/tripleo-image-elements,openstack/tripleo-image-elements,rdo-management/tripleo-image-elements,openstack/tripleo-image-elements,rdo-management/tripleo-image-elements