[llvm] [RISCV] Enable store clustering by default (PR #73796)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `llvm-x86_64-debian-dylib` running on `gribozavr4` while building `llvm` at step 7 "test-build-unified-tree-check-llvm".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/60/builds/10067

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

```
Step 7 (test-build-unified-tree-check-llvm) failure: test (failure)
******************** TEST 'LLVM :: CodeGen/RISCV/orc-b-patterns.ll' FAILED ********************
Exit Code: 1

Command Output (stderr):
--
RUN: at line 2: /b/1/llvm-x86_64-debian-dylib/build/bin/llc -mtriple=riscv32 -verify-machineinstrs < /b/1/llvm-x86_64-debian-dylib/llvm-project/llvm/test/CodeGen/RISCV/orc-b-patterns.ll    | /b/1/llvm-x86_64-debian-dylib/build/bin/FileCheck /b/1/llvm-x86_64-debian-dylib/llvm-project/llvm/test/CodeGen/RISCV/orc-b-patterns.ll -check-prefixes=CHECK,RV32I
+ /b/1/llvm-x86_64-debian-dylib/build/bin/llc -mtriple=riscv32 -verify-machineinstrs
+ /b/1/llvm-x86_64-debian-dylib/build/bin/FileCheck /b/1/llvm-x86_64-debian-dylib/llvm-project/llvm/test/CodeGen/RISCV/orc-b-patterns.ll -check-prefixes=CHECK,RV32I
/b/1/llvm-x86_64-debian-dylib/llvm-project/llvm/test/CodeGen/RISCV/orc-b-patterns.ll:342:15: error: CHECK-NEXT: is not on the line after the previous match
; CHECK-NEXT: sw a2, 0(a1)
              ^
<stdin>:253:2: note: 'next' match was here
 sw a2, 0(a1)
 ^
<stdin>:251:16: note: previous match ended here
 srli a3, a0, 1
               ^
<stdin>:252:1: note: non-matching line after previous match is here
 sub a0, a2, a3
^

Input file: <stdin>
Check file: /b/1/llvm-x86_64-debian-dylib/llvm-project/llvm/test/CodeGen/RISCV/orc-b-patterns.ll

-dump-input=help explains the following input dump.

Input was:
<<<<<<
          .
          .
          .
        248:  addi a2, a2, 514 
        249:  and a0, a0, a2 
        250:  slli a2, a0, 7 
        251:  srli a3, a0, 1 
        252:  sub a0, a2, a3 
        253:  sw a2, 0(a1) 
next:342      !~~~~~~~~~~~  error: match on wrong line
        254:  sw a3, 4(a1) 
        255:  ret 
        256: .Lfunc_end14: 
        257:  .size orc_b_i32_sub_shl8x_x_b1_both_used, .Lfunc_end14-orc_b_i32_sub_shl8x_x_b1_both_used 
        258:  .cfi_endproc 
          .
          .
          .
>>>>>>

--

...

```

</details>

https://github.com/llvm/llvm-project/pull/73796