imagemagick/encoder_icon_fuzzer: Use-of-uninitialized-value in PushColormapIndex

Detailed report: https://oss-fuzz.com/testcase?key=5657487311634432 Project: imagemagick Fuzzer: libFuzzerimagemagickencodericonfuzzer Fuzz target binary: encodericonfuzzer Job Type: libfuzzermsanimagemagick Platform Id: linux Crash Type: Use-of-uninitialized-value Crash Address: Crash State:...