Refactor Scop and ScopBuilder class:
1.Move `hoistInvariantLoads` function from Scop ScopBuilder class.
2. Private functions (`addInvariantLoads,`, `getNonHoistableCtx`) are moved to public section of Scop class. getNonHoistableCtx) are moved to public section of Scop classhoistInvariantLoads function references these functions. hoistInvariantLoads function referencesThese functions will be moved to ScopBuilder as well in these functions next steps.