[Libvir] [PATCH] Fix xen-unified to work in non-root case

Xen-unified introduced a stupid bug, down to me, when running in the non-root case. It didn't keep track of which drivers successfully opened, so will try and perform operations on drivers which didn't open. I suggest that if people approve of the attached patch, then it is applied with some urgency. Rich. -- Emerging Technologies, Red Hat http://et.redhat.com/~rjones/ 64 Baker Street, London, W1U 7DF Mobile: +44 7866 314 421 Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SL4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 Directors: Michael Cunningham (USA), Charlie Peters (USA) and David Owens (Ireland)