bgp_proto_test failure in macos/mavericks. symbol demangle is not workin...

bgp_proto_test failure in macos/mavericks. symbol demangle is not working correctly. e.g. Some of the demangled symbols are 14BgpOpenVersion, 10BgpMsgType, 12BgpMsgLength, etc. Hence check for a partial match only" src/bgp/test/bgp_proto_test.cc