Bug#264262: grub: update-grub for RAID devices

[Michael Stone]

Having multiple entries create for different raid disks strikes me as
silly. If the drive has failed it's gone--at which point the other drive
becomes the boot device and will be bios drive 0. If the situation is
more complicated than that it's going to be too complicated for the
simple groot solution to do any good anyway. Far more useful would be
getting grub-install to not puke if your root is on raid...

Mike Stone