Remove AI_ADDRCONFIG from debugger port binding

Summary: Using AI_ADDRCONFIG makes it difficult to bind server sockets
in mostly IPv6-only environments where it's still expected that loopback
(127.0.0.1) will still work.  getaddrinfo will fail to return 0.0.0.0 as
a valid address to bind to since there are no IPv4 addresses defined
other than 127.0.0.1

See: http://fedoraproject.org/wiki/Networking/NameResolution/ADDRCONFIG

Reviewed By: @ptarjan

Differential Revision: D1395810