fix issue 3193 (fuzz 18644) by adding missing initialization of PPicture's refPic lists
fix issue 3193 (fuzz 18644) by adding missing initialization of PPicture's refPic lists

GuangweiWang/openh264,GuangweiWang/openh264,mstorsjo/openh264,GuangweiWang/openh264,cisco/openh264,cisco/openh264,mstorsjo/openh264,GuangweiWang/openh264,cisco/openh264,cisco/openh264,mstorsjo/openh264,mstorsjo/openh264,cisco/openh264,cisco/openh264,GuangweiWang/openh264,GuangweiWang/openh264,mstorsjo/openh264,mstorsjo/openh264,mstorsjo/openh264,GuangweiWang/openh264,cisco/openh264