Fix some minor resource leaks in PerformRadiusTransaction().

Fix some minor resource leaks in PerformRadiusTransaction().

Failure to free serveraddrs pointed out by Coverity, failure to close
socket noted by code-reading.  These bugs seem to be quite old, but
given the low probability of taking these error-exit paths and the
minimal consequences of the leaks (since the process would presumably
exit shortly anyway), it doesn't seem worth back-patching.

Michael Paquier and Tom Lane