RFR: 8284992: Fix misleading Vector API doc for LSHR operator

[Jie Fu]

Hi all,

The Current Vector API doc for `LSHR` is

Produce a>>>(n&(ESIZE*8-1)). Integral only.


This is misleading which may lead to bugs for Java developers.
This is because for negative byte/short elements, the results computed by `LSHR` will be different from that of `>>>`.
For more details, please see https://github.com/openjdk/jdk/pull/8276#issue-1206391831 .

After the patch, the doc for `LSHR` is

Produce zero-extended right shift of a by (n&(ESIZE*8-1)) bits. Integral only.


Thanks.
Best regards,
Jie

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Commit messages:
 - 8284992: Fix misleading Vector API doc for LSHR operator

Changes: https://git.openjdk.java.net/jdk/pull/8291/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=8291&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8284992
  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/jdk/pull/8291.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/8291/head:pull/8291

PR: https://git.openjdk.java.net/jdk/pull/8291