RFR: 8377438: [VectorAPI] Add new carrier type to LaneType class

[Jatin Bhateja]

As per https://github.com/openjdk/jdk/pull/28002#issuecomment-3789507594 on JDK-8370691 pull request, splitting out portion of PR#28002 into a separate patch.

With Float16 we need to differentiate b/w vector lane element type and carrier type. while element type corresponds to exact type of lane i.e. Float16.class, carrier type corresponds to the storage type required to propagate IEEE 754 float16 values to inline expander.

Patch adds a new carrier type to existing LaneType structure and use it for following purpose.
 - To compute preferred shape of vector.
 - To allocate vector backing storage during dummy vector and iota array creation.
 - Sanity checking to ensure vector lane type is a primitive type in inline expander.

All existing Vector API jtreg test are passing with the patch.

Kindly review and share your feedback.

Best Regards,
Jatin

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Commit messages:
 - 8377438: [VectorAPI] Add new carrier type to LaneType class

Changes: https://git.openjdk.org/jdk/pull/29629/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=29629&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8377438
  Stats: 318 lines in 38 files changed: 233 ins; 1 del; 84 mod
  Patch: https://git.openjdk.org/jdk/pull/29629.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/29629/head:pull/29629

PR: https://git.openjdk.org/jdk/pull/29629