[clang] [clang-tools-extra] [flang] [lld] [llvm] [flang][clang] Add Visibility specific help text for options (PR #81869)

[David Spickett via cfe-commits]

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@@ -93,6 +93,11 @@ class OptionGroup<string name> {
 
 // Define the option class.
 
+class HelpTextForVisibility<OptionVisibility visibility, string text> {
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DavidSpickett wrote:

I've changed it to:
HelpTextForVariants (for a single entry in the list, which is many variants to one string)
Help**Texts**ForVariants (for the list itself, which is many HelpTextForVariants)

Which is bound to confuse someone, but it's that or have them be confused why HelpTextForVariant is actually a many to one mapping which seems worse.

https://github.com/llvm/llvm-project/pull/81869