cleanup log spam for C side ogv
cleanup log spam for C side ogv

partial for https://github.com/brion/ogv.js/issues/205

xzf158/ogv.js,chrislearn/ogv.js,paladox/ogv.js,xzf158/ogv.js,chrislearn/ogv.js,paladox/ogv.js,paladox/ogv.js,chrislearn/ogv.js,xzf158/ogv.js,xzf158/ogv.js,chrislearn/ogv.js,chrislearn/ogv.js,xzf158/ogv.js,paladox/ogv.js,paladox/ogv.js