[clang] [AArch64]: Refactor target parser to use Bitset. (PR #65423)

[via cfe-commits]

================
@@ -552,7 +623,7 @@ struct CpuAlias {
 
 inline constexpr CpuAlias CpuAliases[] = {{"grace", "neoverse-v2"}};
 
-bool getExtensionFeatures(uint64_t Extensions,
+bool getExtensionFeatures(Bitset<AArch64::AEK_EXTENSIONS_MAX> Extensions,
----------------
sdesmalen-arm wrote:

Should `Extensions` be passed as a const reference?

https://github.com/llvm/llvm-project/pull/65423