[clang] [clang][driver] Don't emit an error on an unrecognized SDK name (PR #181897)

[Cyndy Ishida via cfe-commits]

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@@ -2484,6 +2483,8 @@ void Darwin::AddDeploymentTarget(DerivedArgList &Args) const {
   // Read the SDKSettings.json file for more information, like the SDK version
   // that we can pass down to the compiler.
   SDKInfo = parseSDKSettings(getVFS(), Args, getDriver());
+  // FIXME: if SDKInfo is std::nullopt, diagnose a bad isysroot value (e.g.
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cyndyishida wrote:

Nit: The sentence should start with a capital and end with a period. 

I'm surprised this isn't more explicit, but its mentioned in the developer policy. 

> Text formatting and spelling should follow the same rules as documentation and in-code comments, ex capitalization, full stop, etc.

https://llvm.org/docs/DeveloperPolicy.html

https://github.com/llvm/llvm-project/pull/181897