RFR: 8305055: IR check fails on some aarch64 platforms

[Fei Gao]

As @eme64 said in [1], [JDK-8298935](https://bugs.openjdk.org/browse/JDK-8298935) introduced some "collateral damage", disabling the vectorization of some conversions when `+AlignVector`. That affects IR checks of `TestVectorizeTypeConversion.java` and `ArrayTypeConvertTest.java` on some `aarch64` platforms like ThunderX and ThunderX2 [2].

This trivial patch is to allow IR check only when we have `-AlignVector`.

[1] https://github.com/openjdk/jdk/pull/12350#issuecomment-1470065706
[2] https://github.com/openjdk/jdk/blob/7239150f8aff0e3dc07c5b27f6b7fb07237bfc55/src/hotspot/cpu/aarch64/vm_version_aarch64.cpp#L154

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Commit messages:
 - 8305055: IR check fails on some aarch64 platforms

Changes: https://git.openjdk.org/jdk/pull/13236/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=13236&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8305055
  Stats: 14 lines in 2 files changed: 12 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/13236.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/13236/head:pull/13236

PR: https://git.openjdk.org/jdk/pull/13236