fs: query also takes a 'dbg' parameter
fs: query also takes a 'dbg' parameter

Apart from the NBD/mirroring stuff, the smtest now passes.

djs55/message-switch-1,djs55/message-switch,xapi-project/message-switch,djs55/message-switch-1,xapi-project/message-switch,djs55/message-switch,djs55/message-switch-1,djs55/message-switch,xapi-project/message-switch