Reviewed by: Julian Elischer <julian@whistle.com>

Reviewed by:	Julian Elischer <julian@whistle.com>

    Add d_parms() to {c,b}devsw[].  If non-NULL this function points to
    a device routine that will properly fill in the specinfo structure.
    vfs_subr.c's checkalias() supplies appropriate defaults.  This change
    should be fully backwards compatible with existing devices.