[clang] [clang][analyzer] Fix false positive in StdLibraryFunctionsChecker for mmap with MAP_ANON (PR #219568)

[Balázs Benics via cfe-commits]

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@@ -0,0 +1,30 @@
+// RUN: %clang_analyze_cc1 -analyzer-checker=unix.StdCLibraryFunctions \
+// RUN:   -analyzer-config unix.StdCLibraryFunctions:ModelPOSIX=true \
+// RUN:   -triple arm64-apple-darwin -verify=darwin %s
+// RUN: %clang_analyze_cc1 -analyzer-checker=unix.StdCLibraryFunctions \
+// RUN:   -analyzer-config unix.StdCLibraryFunctions:ModelPOSIX=true \
+// RUN:   -triple x86_64-unknown-linux-gnu -verify=linux %s
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steakhal wrote:

Could you hoist the duplicated parts into a `DEFINE` directve?
Also enable the `core` checker package.

https://github.com/llvm/llvm-project/pull/219568