For two FinishRegion nodes, the alias analysis returned "may alias" even
without properly looking through them.

Drive-by-fix: Add meaningful output for --trace-turbo-load-elimination.

R=jarin@chromium.org
BUG=v8:5267

Review-Url: https://codereview.chromium.org/2301903002
Cr-Commit-Position: refs/heads/master@{#39075}