[llvm] [FuncSpec] Relax restrictions on code size growth (PR #196570)

[Momchil Velikov via llvm-commits]

momchil-velikov wrote:

Split out of https://github.com/llvm/llvm-project/pull/195886
Compile time tracker neutral: https://llvm-compile-time-tracker.com/compare.php?from=ed07c92c9629cc64e2b17e82eff841dd238c5218&to=010442acdce9922b791036787687ed1f130d04bb&stat=instructions:u

https://github.com/llvm/llvm-project/pull/196570