[PowerPC][AIX] Support #pragma comment copyright for AIX#1

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tonykuttai wants to merge 4 commits intomandlebug:XCOFFAssociatedMetadatafrom

tonykuttai:tvarghese/pragma-comment-copyright

Commits on Oct 18, 2025

[PowerPC][AIX] Support #pragma comment copyright for AIX
Tony Varghese
committed

Commits on Oct 21, 2025

Addressed the review comments. removed redundant tests
Tony Varghese
committed

Commits on Oct 22, 2025

Pragmas from imported C++20 modules are ignored in the importing translation unit, add backend tests
Tony Varghese
committed

Commits on Oct 29, 2025

Chnaged to platform agnostic names for llvm metadata and variables used
Tony Varghese
committed