[llvm] [llvm][NFC] Use `llvm::sort()` (PR #140335)

[Vladimir Vereschaka via llvm-commits]

vvereschaka wrote:

@el-ev ,

these changes also break the following tests on the ubuntu expensive checks builder here - https://lab.llvm.org/buildbot/#/builders/187/builds/5986

* LLVM::sched-group-barrier-pre-RA.mir
* LLVM::sched-group-barrier-pipeline-solver.mir

would you take care of it?

https://github.com/llvm/llvm-project/pull/140335