src: fix -Wmissing-field-initializers warning

Fix the following (non-serious) compiler warning:

    ../src/node_http_parser.cc:558:1: warning: missing initializer for
    member 'http_parser_settings::on_chunk_header'
    [-Wmissing-field-initializers]
    };
    ^
    ../src/node_http_parser.cc:558:1: warning: missing initializer for
    member 'http_parser_settings::on_chunk_complete'
    [-Wmissing-field-initializers]

Introduced in commit b3a7da10 ("deps: update http_parser to 2.5.0").

PR-URL: https://github.com/iojs/io.js/pull/1606


Reviewed-By: Fedor Indutny <fedor@indutny.com>