[llvm] [IR] Add getDataLayout() helpers to BasicBlock and Instruction (PR #96902)

[Yingwei Zheng via llvm-commits]

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@@ -218,6 +219,11 @@ class BasicBlock final : public Value, // Basic blocks are data objects also
                             static_cast<const BasicBlock *>(this)->getModule());
   }
 
+  /// Get the data layout of the module this instruction belongs to.
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dtcxzyw wrote:

```suggestion
  /// Get the data layout of the module this basic block belongs to.
```

https://github.com/llvm/llvm-project/pull/96902