gio: don't accept nonstandard IPv4 "numbers-and-dots" addresses
In addition to the standard "192.168.1.1" format, there are numerous
legacy IPv4 address formats (such as "192.168.257",
"0xc0.0xa8.0x01.0x01", "0300.0250.0001.0001", "
3232235777", and
"0xc0a80101"). However, none of these forms are ever used any more
except in phishing attempts. GLib wasn't supposed to be accepting
these addresses (neither g_hostname_is_ip_address() nor
g_inet_address_new_from_string() recognizes them), but getaddrinfo()
accepts them, and so the parts of gio that use getaddrinfo()
accidentally did accept those formats.
Fix GNetworkAddress and GResolver to reject these address formats.
https://bugzilla.gnome.org/show_bug.cgi?id=679957