Creates the mountpoints for the standard api filesystems in /etc/fstab.
At the moment this is already done by /lib/udev/devices in our udev
package. However, with this change it is possible to boot a fully
working system with the udev unaltered from upstream.
For the future, this patch allows us to get rid of the /lib/udev/devices
directory from the udev package alltogether.
Signed-off-by: Tom Gundersen