[llvm] [BOLT] Add --pad-funcs-before=func:n (PR #117924)

[Maksim Panchenko via llvm-commits]

================
@@ -94,6 +100,30 @@ size_t padFunction(const BinaryFunction &Function) {
   return 0;
 }
 
+size_t padFunctionBefore(const BinaryFunction &Function) {
----------------
maksfb wrote:

How similar is the code to `padFunction()`? Can you reduce the code duplication?

https://github.com/llvm/llvm-project/pull/117924