Fix potential mem leak when there are errors.
Fix potential mem leak when there are errors.

DeadAlready/node-geoip2,michaelkyriacou/node-geoip2,davidtsai/node-geoip2,DeadAlready/node-geoip2,davidtsai/node-geoip2,michaelkyriacou/node-geoip2,michaelkyriacou/node-geoip2,davidtsai/node-geoip2,DeadAlready/node-geoip2