Generic file system mounting

by stacktic for The NetBSD Project

This application is in relation with the following project idea : http://www.netbsd.org/contrib/soc-projects.html#xmount. The aim of this project is to get rid of the opaque data container when calling mount(2). This will allow to mount a file system without knowing the type. To do so, it will be necessary to add a new vfs operation which determines whether the parameters can be handled by the file system.