[clang-tools-extra] [clang-tidy] Add AllowExplicitReferencedInitialValues to `readability-enum-initial-value` (PR #189459)

[Björn Svensson via cfe-commits]

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@@ -13,8 +13,8 @@
 
 namespace clang::tidy::readability {
 
-/// Enforces consistent style for enumerators' initialization, covering three
-/// styles: none, first only, or all initialized explicitly.
+/// Enforces consistent style for enumerators' initialization, covering four
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bjosv wrote:

Sounds fair. Reverted this change since this is an added exception.

https://github.com/llvm/llvm-project/pull/189459