[issue1622] devfs doesn't create my ad4s3 (macbook)

[Matthew Dillon]

    Ooh, it also occurs to me that we could change the construction of
    the device name instead of overloading 's#' to remove the confusion.
    So for a native GPT we could call it 's0.<index>' instead of 's<index>'.
    Or perhaps we could just call it 'g<index'> instead of 's<index>', so
    something like:  ad4g0, ad4g1, ad4g2, ad4g3.

    Just throwing out ideas.

					-Matt