RFR: 8267370: [Vector API] Fix several crashes after JDK-8256973

[Jie Fu]

On Wed, 19 May 2021 09:46:16 GMT, Jatin Bhateja <jbhateja at openjdk.org> wrote:

> Thanks much for providing a quick fix. Problem here seems to be related to assert in following assembler routines which made an assumption that the instruction is only supported over AVX2 platforms.

Good catch! @jatin-bhateja 
It makes sense to enable 128-bit vectors for vpmovmskb.
Updated.

More testing is in progress.
Will let you know once finished.
Thanks.

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PR: https://git.openjdk.java.net/jdk/pull/4109