XL: Move '-bE:' flag earlier so it can be overridden.
By default, we generate an export list for a shared library and pass that file on the link line. The problem was that it could not be overridden by a target when a specific export file is being used. Multiple -bE flags on the link are overridden by subsequent -bE flags, so only the last one is used.
Fixes: #13282 (closed)
Topic-rename: xl-early-bE
Edited by Brad King