[Soekris] _Problem_MBR

[Stuart Henderson]

> BootDrive = 80 81 F0 FF

This sets the boot order. Since there's an MBR on the drive
it's being booted, but you didn't make any partition active
hence the error from the MBR.

To force PXE-boot this time only, `boot f0'.
To force it always, change BootDrive.

This is mentioned in the release notes for whichever
version introduced BootDrive (it's one of the more recent
ones).