[clang] [clang][Sema] Stop format size estimator upon %p to adapt to linux kernel's extension (PR #65969)

[Nick Desaulniers via cfe-commits]

nickdesaulniers wrote:

ping @hazohelet . This should be good to land and should help clear some red in our CI for Linux kernel builds.

https://github.com/llvm/llvm-project/pull/65969