[clang] [flang] Ignore -f[no-]realloc-lhs. (PR #120320)

[Kiran Chandramohan via cfe-commits]

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@@ -3465,7 +3465,7 @@ defm diagnostics_show_line_numbers : BoolFOption<"diagnostics-show-line-numbers"
   PosFlag<SetTrue>>;
 def fno_realloc_lhs : Flag<["-"], "fno-realloc-lhs">, Group<f_Group>,
   HelpText<"An allocatable left-hand side of an intrinsic assignment is assumed to be allocated and match the shape/type of the right-hand side">,
-  Visibility<[FlangOption, FC1Option]>;
+  Visibility<[ClangOption, CLOption, FlangOption, FC1Option]>;
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kiranchandramohan wrote:

Would this now show up in `clang --help` and online guide? Is that what we want?
Is CLOption for Windows?

https://github.com/llvm/llvm-project/pull/120320