[clang] Add tests for driver to propagate module map flags even without -fmod… (PR #75827)

[Fangrui Song via cfe-commits]

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@@ -57,6 +57,14 @@
 // CHECK-MODULE-MAP-FILES: "-fmodule-map-file=foo.map"
 // CHECK-MODULE-MAP-FILES: "-fmodule-map-file=bar.map"
 
+// RUN: %clang -fno-modules -fmodule-name=foo -c -### %s 2>&1 | FileCheck -check-prefix=CHECK-PROPAGATE-MODULE-NAME %s
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MaskRay wrote:

Add some comment about the behavior?

https://github.com/llvm/llvm-project/pull/75827