[compiler-rt] [compiler-rt] Define `__STDC_FORMAT_MACROS` to ensure `PRId64` is available (PR #102980)

[Mosè Giordano via llvm-commits]

giordano wrote:

> I think your email address is still the GitHub alias @giordano

No, it's not: https://github.com/llvm/llvm-project/commit/098147142661a6b3ce058f92a2a0a958cdcef15c.patch.  

> See https://github.com/llvm/llvm-project/pull/102980#issuecomment-2284928642

I don't think that check ran again after I pushed, since it's triggered only on pull-request opening: https://github.com/llvm/llvm-project/blob/277ca48f2f2ab78290c0702d45b6db54a32c99cf/.github/workflows/email-check.yaml#L3-L6

https://github.com/llvm/llvm-project/pull/102980