DFAContentModel::buildDFA(): correctly zero-initialize fFollowList

Due to a copy&paste issue, the intended zero-initialization of
fFollowList wasn't done (copy&paste issue), and thus in case of
OutOfMemory exception when initializing the array, the memory freeing in
cleanup() could access uninitialized elements.

Follow-up of https://github.com/apache/xerces-c/pull/40 / a65990d79d3fc333d7481f010da4e165a88b6cb3

Fixes GDAL's https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=42636
1 file changed