To restore the normal boot of a AIX box on a system that is not managed by a HMC perform the following.
# bootlist -m normal hdisk0 cd0
To verify the settings:
# bootlist -m normal -o hdisk0 blv=hd5 pathid=2 cd0
This will let the system boot from hdisk0 as the first boot device and cd0 as the second boot device.