[clang] [clang][Sema] Fix typo in 'offsetof' diagnostics (PR #133448)

[Aaron Ballman via cfe-commits]

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@@ -7031,10 +7031,10 @@ def err_offsetof_incomplete_type : Error<
 def err_offsetof_record_type : Error<
   "offsetof requires struct, union, or class type, %0 invalid">;
 def err_offsetof_array_type : Error<"offsetof requires array type, %0 invalid">;
-def ext_offsetof_non_pod_type : ExtWarn<"offset of on non-POD type %0">,
+def ext_offsetof_non_pod_type : ExtWarn<"offsetof on non-POD type %0">,
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AaronBallman wrote:

```suggestion
def ext_offsetof_non_pod_type : ExtWarn<"'offsetof' on non-POD type %0">,
```

https://github.com/llvm/llvm-project/pull/133448