reset ci->retc when pic_receive is called
reset ci->retc when pic_receive is called

ktakashi/picrin,ktakashi/picrin,omasanori/picrin,dcurrie/picrin,dcurrie/picrin,koba-e964/picrin,picrin-scheme/picrin,omasanori/picrin,leavesbnw/picrin,koba-e964/picrin,ktakashi/picrin,leavesbnw/picrin,koba-e964/picrin,picrin-scheme/picrin,leavesbnw/picrin