graphicsmagick:coder_MNG_fuzzer: Use-of-uninitialized-value in SetImageEx

Project: http://hg.code.sf.net/p/graphicsmagick/code Detailed Report: https://oss-fuzz.com/testcase?key=6605751487627264 Project: graphicsmagick Fuzzing Engine: libFuzzer Fuzz Target: coderMNGfuzzer Job Type: libfuzzermsangraphicsmagick Platform Id: linux Crash Type: Use-of-uninitialized-value...