get -Wformat-truncation and -Wformat-overflow re-enabled

[nickdesaulniers]

Looks like Linus just turned this off in bd664f6.

I suspect that Linus was hitting https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78512#c7 (i.e. the kernel's use of %p with additional non-standard modifiers) which was eventually disabled in GCC.

We hit this in ClangBuiltLinux#1923 because clang had the same checks under a different flag name -Wfortify-source. This is getting fixed in llvm/llvm-project#65969.

These issues still persist (compile time detection of the use of snprintf that result in unconditional truncation). These should be fixed; they're not compiler specfic though, as noted by @nathanchance here. So filing this TODO here so that we can close ClangBuiltLinux#1923 once llvm/llvm-project#65969 lands.

[nickdesaulniers]

As noted by @kees in https://lore.kernel.org/llvm/202308291147.2CB91AB9@keescook/, some of these usages may need larger refactorings, such as the usage of sysfs_emit.