When getaddrinfo returns and error, the contents
of ai are invalid so we cannot continue based
on their data structures.

In the previous branch of the if statement, we
abort there if there is an error so for consistency
we abort here too.

The test case fixes the port number to UINTMAX32
for both an enumberated bind-address and the
default bind-address covering the two calls to
getaddrinfo.

Review thanks Sanja.