curl: 57: Heap out-of-bounds read in `curl_easy_escape_ccsid()` / `curl_easy_unescape_ccsid()`

Summary curleasyescapeccsid and curleasyunescapeccsid in projects/OS400/ccsidcurl.c discard the converted byte count returned by dynconvert and pass 0 to the downstream curleasyescape / curleasyunescape. When the caller supplies a positive explicit length with non-NUL-terminated input, dynconvert...