Overcloud node deployment fails with a dracut emergency shell

Issue

• When trying to deploy a baremetal node the deployment process fails with an error of unable to find disk and will exit to a dracut emergency shell.

• The following error message are displayed:

[   77.793696] localhost dracut-pre-mount[910]: Could not find disk to use.
[   77.793951] localhost dracut-pre-mount[910]: Starting troubleshooting shell.

You might want to save "/run/initramfs/rdsosreport.txt" to a  
USB stick or /boot after mounting them and attaching it to a  
bug report.