[clang] [clang][driver][darwin] Use DefaultDeploymentTarget when inferring deployment target from SDK (PR #217983)

[Ian Anderson via cfe-commits]

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@@ -0,0 +1,21 @@
+// Ensure that the deployment target inferred from the SDK when none is
+// specified on the command line uses "DefaultDeploymentTarget" rather than
+// "Version" when the SDK specifies both and they differ.
+
+// RUN: rm -rf %t/SDKs/iPhoneOS18.0.sdk
+// RUN: mkdir -p %t/SDKs/iPhoneOS18.0.sdk
+// RUN: echo '{"CanonicalName": "iphoneos18.0", "Version": "18.0", "DefaultDeploymentTarget": "17.0", "MaximumDeploymentTarget": "18.0.99"}' \
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ian-twilightcoder wrote:

This is missing a lot of the important keys, I know it doesn't matter for this test but I've been trying to be consistent about test SDKSettings like in clang/test/Driver/darwin-invalid-version-range.c, can we copy that please?

https://github.com/llvm/llvm-project/pull/217983