RFR: 8323577: C2 SuperWord: remove AlignVector restrictions on IR tests added in JDK-8305055

[Emanuel Peter]

These IR rules were restricted in [JDK-8305055](https://bugs.openjdk.org/browse/JDK-8305055), [PR for comparison](https://git.openjdk.org/jdk/pull/13236).

This had to be done because those cases were no longer vectorized with `AlignVector` after my bugfix [JDK-8298935](https://bugs.openjdk.org/browse/JDK-8298935), they were "collateral damage". Before this bugfix, we would vectorize, even though the alignment constraints had rejected some memops, but then they were re-intriduced during pair extension. This re-introduction led to this bug for other reasons. I proposed to restore vectorization (i.e. fix the "collateral damage") by improving alignment-constraints ([JDK-8303827](https://bugs.openjdk.org/browse/JDK-8303827)).

Since I had to already completely rework the alignment constraints because of a bug, I relaxed the constraints:
[JDK-8310190](https://bugs.openjdk.org/browse/JDK-8310190)

Now I can remove the restrictions on those rules.

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Commit messages:
 - 8323577

Changes: https://git.openjdk.org/jdk/pull/17369/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=17369&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8323577
  Stats: 13 lines in 2 files changed: 0 ins; 12 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/17369.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/17369/head:pull/17369

PR: https://git.openjdk.org/jdk/pull/17369