[IslAst] Untangle IslAst lit-testcases from specifics of the legacy-PM
Summary:
This consists instances of two changes:
- Accept any order of checks for a specific loop form, that appear in different order in the new vs legacy-PM.
- Remove checks for specific regions.
Reviewers: grosser
Reviewed By: grosser
Subscribers: pollydev, llvm-commits
Tags: #polly
Differential Revision: https://reviews.llvm.org/D35837
git-svn-id: https://llvm.org/svn/llvm-project/polly/trunk@308976 91177308-0d34-0410-b5e6-96231b3b80d8