geoip: Fix memory leak when using GeoIPRecord
GeoIP_record_by_ipnum{,_v6} returns allocated pointer to
GeoIPRecord with allocated city, region & postal_code which is
not freed after the call.
Fixed by xstrdup-ing required GeoIPRecord member (city/region) and
after calling GeoIPRecord_delete to free the geoip record.
Of course it is needed to also free obtained city/region in netsniff-ng,
astraceroute & flowtop tools.
Fixes #169
Signed-off-by: Vadim Kochan <vadim4j@gmail.com>
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>