Remove obsolete quickening-related TODO comments. am: 79f9e3647b am: 016b707efe

Original change: https://android-review.googlesource.com/c/platform/art/+/2984732

Change-Id: I7aae69dd7c0559e3f09cd3fc83ca0204e846d5ac
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>