[llvm] [MIR2Vec] Add MIR support to triplet generator script (PR #164332)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `ppc64le-flang-rhel-clang` running on `ppc64le-flang-rhel-test` while building `llvm` at step 7 "test-build-unified-tree-check-flang-rt".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/157/builds/41760

<details>
<summary>Here is the relevant piece of the build log for the reference</summary>

```
Step 7 (test-build-unified-tree-check-flang-rt) failure: 1200 seconds without output running [b'ninja', b'check-flang-rt'], attempting to kill
...
20.550 [2/8/33] Building CXX object flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/Format.cpp.o
21.911 [2/7/34] Building CXX object flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/CommandTest.cpp.o
24.625 [2/6/35] Building CXX object flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/Complex.cpp.o
24.828 [2/5/36] Building CXX object flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/NumericalFormatTest.cpp.o
26.620 [2/4/37] Building CXX object flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/ExternalIOTest.cpp.o
26.974 [2/3/38] Building CXX object flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/Transformational.cpp.o
36.997 [2/2/39] Building CXX object flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/CharacterTest.cpp.o
54.901 [2/1/40] Building CXX object flang-rt/unittests/Runtime/CMakeFiles/RuntimeTests.dir/Reduction.cpp.o
58.840 [1/1/41] Linking CXX executable flang-rt/unittests/Runtime/RuntimeTests
58.841 [0/1/41] Running the Flang-RT regression tests
command timed out: 1200 seconds without output running [b'ninja', b'check-flang-rt'], attempting to kill
process killed by signal 9
program finished with exit code -1
elapsedTime=1267.166486

```

</details>

https://github.com/llvm/llvm-project/pull/164332