[arch-general] iniitcpio root device check

[Dave Reisner]

>Ok, I renamed "9p_mount_handler" to  "ninep_mount_handler" and updated
>mount_handler= accordingly, and rebuild the initcpio images.
>
>Still no joy... :)
>
>I went so far as to rename 9p to ninep in
>/lib/initcpio/{install,hooks} and the HOOKS string, and rebuilt the
>initcpio images, but that did not help.
>
>Dwight

Let's try this one more time. You're missing a pointer to your install
script. Part of the build function needs:

SCRIPT=ninep

or whatever you're calling it...

d