[lld] [LLD][MinGW] Exclude load config symbols from auto-export (PR #126134)

[Martin Storsjö via llvm-commits]

https://github.com/mstorsjo approved this pull request.

LGTM. I had forgotten the fact that these normally are excluded by the logic for excluding anything from the CRT, so the effect is smaller than I thought when I saw the recent testcase.

https://github.com/llvm/llvm-project/pull/126134