8380448: Split VM_Version::get_processor_features() in vm_version_x86.cpp into multiple helper routines

[ashu-mehra]

This patch is reorganizing the code to split get_processor_features() into multiple helper functions. Details are present in the issue https://bugs.openjdk.org/browse/JDK-8380448.
It should not change the behavior of any VM flag, except UseVectorizedHashCodeIntrinsic. The earlier code always set UseVectorizedHashCodeIntrinsic to true if UseAVX >= 2. That means specifying -XX:-UseVectorizedHashCodeIntrinsic on command line wouldn't disable use of this intrinsic. This looks like a bug and has been fixed in this patch.

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Issue

• JDK-8380448: Split VM_Version::get_processor_features() in vm_version_x86.cpp into multiple helper routines (Enhancement - P4)

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[ashu-mehra]

I have included the changes for #31284 in this PR to avoid hitting teat failures that #31284 is fixing.

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[openjdk]

@ashu-mehra this pull request can not be integrated into master due to one or more merge conflicts. To resolve these merge conflicts and update this pull request you can run the following commands in the local repository for your personal fork:

git checkout vm_version_x86-reorg
git fetch https://git.openjdk.org/jdk.git master
git merge FETCH_HEAD
# resolve conflicts and follow the instructions given by git merge
git commit -m "Merge master"
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Webrevs

• 03: Full - Incremental (be8cb4bc)
• 02: Full - Incremental (b568a9a3)
• 01: Full (53956df4)
• 00: Full (2f2889ed)