[clang] [clang][Interp] Fix IntAP(s) to IntAP(s) casts (PR #69915)

[Aaron Ballman via cfe-commits]

https://github.com/AaronBallman approved this pull request.

LGTM but please add the description to the patch commit message when landing.

https://github.com/llvm/llvm-project/pull/69915