c703913 Remove non-existant 'wiremode' attribute

Authored and Committed by berrange 6 years ago
    Remove non-existant 'wiremode' attribute
    
    The 'wiremode' attribute exists in a couple of Xen XML files, but no code has
    ever parsed that value. It was later added to the RNG schema too, again despite
    there not being any code which parses it.
    
    Reviewed-by: Jim Fehlig <jfehlig@suse.com>
    Signed-off-by: Daniel P. Berrange <berrange@redhat.com>