[llvm] [Bolt] Fix address translation for KASLR kernel (PR #114261)

[Maksim Panchenko via llvm-commits]

maksfb wrote:

> What is the symptom of the breakage? Can you share the perf file and the vmlinux so that I can debug? I just tried my patch on 6.12.0-rc6-1 for non-KASLR profile and it generated exactly the same bolt profile using perf2bolt without my patch. 

On your system you must have matched `vmlinux` binary by build-id. When build-id doesn't match or doesn't exist, with this patch `perf2bolt` will try to match the kernel binary by name. In `perf.data` it's recorded as "[kernel.kallsyms]" hence the error from `perf2bolt`. The workaround is to rename "vmlinux" to "[kernel.kallsyms]" which I'd rather avoid since unlike in the user space there's no ambiguity about the kernel binary.

https://github.com/llvm/llvm-project/pull/114261