Bump llvm-project from ff7d639 to b46c5b7

Bumps [llvm-project](https://github.com/Xilinx/llvm-project) from `ff7d639` to `b46c5b7`.
- [Commits](Xilinx/llvm-project@ff7d639...b46c5b7)

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

Signed-off-by: dependabot[bot] <support@github.com>