[llvm-branch-commits] [BOLT][NFC] Simplify YAMLProfileWriter::convert (PR #82129)

[Amir Ayupov via llvm-branch-commits]

https://github.com/aaupov created https://github.com/llvm/llvm-project/pull/82129

Use `getAnnotationWithDefault` instead of testing if the annotation is
set. If the default value is used, and `CSI.Count` is set to zero, the
target is discarded by a check below.

Test Plan: NFC