[clang] [compiler-rt] [clang-tools-extra] [PGO] Reland PGO's Counter Reset and File Dumping APIs #76471 (PR #78285)

[Qiongsi Wu via cfe-commits]

qiongsiwu wrote:

> This patch broke both the [Solaris/sparcv9](https://lab.llvm.org/buildbot/#/builders/72/builds/2015) and [Solaris/amd64](https://lab.llvm.org/staging/#/builders/94/builds/394) buildbots.
> 
> If it really requires recent `lld`, this is guaranteed to not work: `lld` hasn't even been ported to Solaris. Similar issues most likely will exist on other targets where the bot either doesn't build `lld` or it isn't supported at all.

Thanks for the note @rorth . I will investigate today. This PR in itself does not require `lld`. 

https://github.com/llvm/llvm-project/pull/78285