[llvm] [Mips] Support llvm.readcyclecounter intrinsic (PR #114953)

[via llvm-commits]

yingopq wrote:

> I reverted this commit. @yingopq can you have a look at this problem?

I try to reproduce this failure, but the result was OK.
```
root at debian-sid-amd64:~/llvm-project# ./build/bin/llvm-lit -v llvm/test/CodeGen/Mips/readcyclecounter.ll
-- Testing: 1 tests, 1 workers --
PASS: LLVM :: CodeGen/Mips/readcyclecounter.ll (1 of 1)

Testing Time: 0.11s

Total Discovered Tests: 1
  Passed: 1 (100.00%)
root at debian-sid-amd64:~/llvm-project# cat /proc/version
Linux version 5.19.0-40-generic (buildd at lcy02-amd64-047) (x86_64-linux-gnu-gcc (Ubuntu 11.3.0-1ubuntu1~22.04) 11.3.0, GNU ld (GNU Binutils for Ubuntu) 2.38) #41~22.04.1-Ubuntu SMP PREEMPT_DYNAMIC Fri Mar 31 16:00:14 UTC 2

```

I would commit a change.

https://github.com/llvm/llvm-project/pull/114953