[llvm] [RISCV] Correct the spelling of the Zcmop mnemonics. (PR #88826)

[Yingwei Zheng via llvm-commits]

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@@ -1,7 +1,7 @@
-# RUN: not llvm-mc -triple riscv32 -mattr=+zcmop < %s 2>&1 | FileCheck %s
+# RUN: not llvm-mc -triple riscv32 -mattr=+zc.mop < %s 2>&1 | FileCheck %s
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dtcxzyw wrote:

```suggestion
# RUN: not llvm-mc -triple riscv32 -mattr=+zcmop < %s 2>&1 | FileCheck %s
```

https://github.com/llvm/llvm-project/pull/88826