Rollup merge of #113692 - krasimirgg:llvm-17-no-opaque, r=nikic

tests: adapt for removal of -opaque-pointers in LLVM 17

The commit llvm/llvm-project@53717ca removed the flag from LLVM.

Found via our experimental rust + LLVM@HEAD bot: https://buildkite.com/llvm-project/rust-llvm-integrate-prototype/builds/20777#01895454-40b2-4e2f-978b-1294a83e1cce

Author: matthiaskrgr