Can't boot after make installworld

[Dan Naumov]

The ZFS bootloader has been changed in 8-STABLE compared to
8.0-RELEASE. Reinstall your boot blocks.

P.S: "LOADER_ZFS_SUPPORT=YES" is also deprecated in 8-STABLE, not to
mention that you have it in the wrong place, for 8.0, it goes into
make.conf, not src.conf.

Is there any particular reason you are upgrading from a production
release to a development branch of the OS?

- Sincerely,
Dan Naumov