GBDE on geom_stripe cannot be manually detached

[Daniel Eriksson]

If you create a geom_stripe device (/dev/stripe/somename) and then set
up GBDE on that device, manually detaching GBDE fails.

'gbde init' and 'gbde attach' works just fine:

/dev/stripe/:
crw-r-----  1 root  operator    4, 119 Jul  3 21:57 stripe_500GB
crw-r-----  1 root  operator    4, 141 Jul  3 22:59 stripe_500GB.bde

I've tried:
gbde detach stripe_500G
gbde detach stripe/stripe_500G
gbde detach /dev/stripe/stripe_500G

All fail with the same type of error:
gbde: Detach of stripe_500G failed: Geom not found

This is on a machine running CURRENT from earlier today.

/Daniel Eriksson