Update 'Device address' section to describe 'zpci' element and
its two attributes 'uid' and 'fid'.
Signed-off-by: NYi Min Zhao <zyimin@linux.ibm.com>
Reviewed-by: NBoris Fiuczynski <fiuczy@linux.ibm.com>
Reviewed-by: NStefan Zimmermann <stzi@linux.ibm.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NAndrea Bolognani <abologna@redhat.com>