Rollup merge of #129749 - krasimirgg:llvm-20-lto, r=nikic

llvm-wrapper: adapt for LLVM API changes

No functional changes intended.

Updates the wrapper for 5c4lar/llvm-project@21eddfa.

````@rustbot```` label: +llvm-main
r? ````@nikic````

Author: matthiaskrgr