[llvm-branch-commits] [CI] Refactor out some early exits in compute_projects (PR #143478)

[Aiden Grossman via llvm-branch-commits]

https://github.com/boomanaiden154 created https://github.com/llvm/llvm-project/pull/143478

I have a habit of using early exits given it is in the LLVM coding
standards, but most of the early exits used within this script were
trivial and actually adding complexity. These are all instances where we
only perform one operation after the early exit, so removing the early
exit means less lines of code and arguably more readable code.