[mlir] Re-land Loosen restrictions on folding dynamic reshapes#142827

AGindinson merged 2 commits intomainllvm/llvm-project:mainfrom

revert-142639-revert-137963-reassoc-expand-of-collapsellvm/llvm-project:revert-142639-revert-137963-reassoc-expand-of-collapseCopy head branch name to clipboard