Remove 128.0.0.0/16 and 191.255.0.0/16 from the reserved list.

These were returned to the general allocation pool by RFC 3330, and hence
shouldn't cause an IP address validation failure due to being reserved. At
least 128.0.0.0/16 is in use on the public Internet today.

Fixes bug #66229 (128.0.0.0/16 isn't reserved any longer).