[llvm] [RISCV] Assert extensions are sorted at compile time. NFCI (PR #77442)

[Luke Lau via llvm-commits]

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@@ -1062,79 +1059,82 @@ static const char *ImpliedExtsZvl65536b[] = {"zvl32768b"};
 static const char *ImpliedExtsZvl8192b[] = {"zvl4096b"};
 
 struct ImpliedExtsEntry {
-  StringLiteral Name;
+  const char *Name;
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lukel97 wrote:

I changed this because StringLiteral didn't have a constexpr `<` operator. But I took another stab at this, and I think we can actually make the StringLiteral std::string_view operator constexpr. 

https://github.com/llvm/llvm-project/pull/77442