[clang] [clang-tools-extra] [lld] [llvm] [llvm] Add subcommand support for OptTable (PR #155026)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `ppc64le-lld-multistage-test` running on `ppc64le-lld-multistage-test` while building `clang-tools-extra,clang,lld,llvm` at step 12 "build-stage2-unified-tree".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/168/builds/16524

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

```
Step 12 (build-stage2-unified-tree) failure: build (failure) (timed out)
...
724.765 [57/9/6658] Linking CXX executable unittests/Target/TargetMachineCTests
725.171 [57/8/6659] Linking CXX executable bin/llvm-split
725.172 [57/7/6660] Linking CXX executable bin/llc
725.682 [57/6/6661] Linking CXX executable bin/llvm-dwp
728.082 [57/5/6662] Linking CXX executable tools/lld/unittests/AsLibAll/LLDAsLibAllTests
728.501 [57/4/6663] Linking CXX executable bin/bugpoint
730.815 [56/4/6664] Linking CXX executable bin/opt
737.613 [56/3/6665] Linking CXX executable bin/lld
752.341 [56/2/6666] Building CXX object tools/bugpoint-passes/CMakeFiles/BugpointPasses.dir/TestPasses.cpp.o
755.454 [55/2/6667] Linking CXX shared module lib/BugpointPasses.so
command timed out: 1200 seconds without output running [b'ninja'], attempting to kill
process killed by signal 9
program finished with exit code -1
elapsedTime=1956.112859

```

</details>

https://github.com/llvm/llvm-project/pull/155026