[vectorIntrinsics+fp16] RFR: 8277304: Java support for FP16

[Smita Kamath]

Initial FP16 vectorAPI Java support.

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Commit messages:
 - Fixed space and tabs in code
 - FP16 Java support

Changes: https://git.openjdk.java.net/panama-vector/pull/164/files
 Webrev: https://webrevs.openjdk.java.net/?repo=panama-vector&pr=164&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8277304
  Stats: 9566 lines in 22 files changed: 9451 ins; 7 del; 108 mod
  Patch: https://git.openjdk.java.net/panama-vector/pull/164.diff
  Fetch: git fetch https://git.openjdk.java.net/panama-vector pull/164/head:pull/164

PR: https://git.openjdk.java.net/panama-vector/pull/164