build(deps): bump llvm-project from 7820460 to cb664e8

Bumps [llvm-project](https://github.com/Xilinx/llvm-aie) from `7820460` to `cb664e8`.
- [Release notes](https://github.com/Xilinx/llvm-aie/releases)
- [Commits](Xilinx/llvm-aie@7820460...cb664e8)

---
updated-dependencies:
- dependency-name: llvm-project
  dependency-version: cb664e8cc3eb42a12e3ad3cee28729785ffa97a3
  dependency-type: direct:production
...

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Author: dependabot[bot]