Back when the --icf= option was hooked up in the MinGW frontend in LLD,
in 2017, lld-link didn't support safe ICF, and mapping it to noicf was
suggested in review: https://reviews.llvm.org/D40019
In 2018, in ab038025a50c79a89edb5832b163e8c729ceb703,
lld-link did get support for handling address significance tables,
allowing the ICF to operate safely on more sections.
Later in 2021, lld-link did get support for a separate safe ICF mode in
5bdc5e7efda4100c4d11085c2da8f1fb932ccce4 /
https://reviews.llvm.org/D97436.
Hook this up for the MinGW frontend as well.
6d66440c50