Heads up - minor usb disk key probing change

[Matthew Dillon]

    USB disk keys in the master branch will now attach starting
    at da8 instead of da0.  This is to reduce interference between
    USB disk keys and AHCI/SILI probes which also attach to da*.

    The relatively few people booting from USB disk keys will need
    to adjust the /etc/fstab on the disk key.

    The kernel should still be able to automount the root but you can
    avoid unnecessary root mount scanning by supplying the exact mount
    string via /boot/loader.conf, e.g. vfs.root.mountfrom="ufs:da8s1a".

					-Matt
					Matthew Dillon 
					<dillon at backplane.com>