[clang] [Matrix] Add a row\col major toggle in the clang driver (PR #167628)

[Florian Hahn via cfe-commits]

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@@ -13006,6 +13006,8 @@ def err_builtin_trivially_relocate_invalid_arg_type: Error <
 
 def err_builtin_matrix_disabled: Error<
   "matrix types extension is disabled. Pass -fenable-matrix to enable it">;
+def err_builtin_matrix_major_order_disabled: Error<
+  "matrix %select{row|column}0 major %select{load|store}1 is disabled. Pass -fmatrix-memory-layout=%select{row|column}0-major to enable it">;
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fhahn wrote:

```suggestion
  "matrix %select{row|column}0 major %select{load|store}1 is not supported with -fmatrix-memory-layout=%select{row|column}0-major. Pass -fmatrix-memory-layout=%select{row|column}0-major to enable it">;
```

would be good to say it's not supported with the passed flag. Also might be easier to just mentioned the full builtin name.

https://github.com/llvm/llvm-project/pull/167628