Use hvparams in GetInstanceInfo

Use hvparams in GetInstanceInfo

This patch extends the GetInstanceInfo function of the
hypervisors by an hvparams parameters. This leads to
an extension of the instance_info RPC call and the
adjustmend of all classes using this call.

Signed-off-by: Helga Velroyen <helgav@google.com>
Reviewed-by: Thomas Thrainer <thomasth@google.com>