Since we want a vinum geom created anytime the module loads, move the
geom creation to a seperate init function and ignore the tasting.
The config is now parsed only in the vinumdrive geom, which hopefully
fixes the problem, that the drive class tasted before the vinum class
had a chance, for good.
Also restore the behaviour that the module can be loaded at boot time
and on a running system.
--
Check for g_read_data(9) errors properly; don't pass error value
pointer to g_read_data(9) at all if we don't have any use of it.
0ed7cd39d9