Bump llvm-project from 18197f9 to 63401e3

Bumps [llvm-project](https://github.com/Xilinx/llvm-project) from `18197f9` to `63401e3`.
- [Commits](Xilinx/llvm-project@18197f9...63401e3)

---
updated-dependencies:
- dependency-name: llvm-project
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>