Add AOCC 5.2.0 to install config

AMD confirmed by email that AOCC 5.2 meets our licence requirements.
5.2.0 uses the newer URL pattern (4.1+). Verified end-to-end: tarball
downloads, extracts as XZ despite the .tar extension, and check_exe
passes (reports AMD clang 17.0.6 / AOCC_5.2.0).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: mattgodbolt

bin/yaml/cpp.yaml

@@ -1235,6 +1235,9 @@ compilers:
           - name: 5.1.0
             major: 5
             minor: 1
+          - name: 5.2.0
+            major: 5
+            minor: 2
     plugins:
       clad:
         path_name: clang-plugins/clad-{{name}}