[code-reflection] RFR: [hat] F16 object creation within device code via F16.of

[Juan Fumero]

FP16 matmul supported. 

Example:


F16Array.F16 ha = a.array(kernelContext.gix);
F16Array.F16 initVal = F16.of( 2.1f);
// store new half value
ha.value(initVal.value());


How to test:


java @hat/test ffi-opencl hat.test.TestFP16Type -DHAT=SHOW_COMPILATION_PHASES -DTRACE_CALLSITES=true

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Commit messages:
 - [hat] Include vmoptions in the hat single test
 - [hat] jextracted OpenCLHatKernelBuilder fixed
 - Merge branch 'code-reflection' into hat/fp16/init
 - [hat] New test for float initialization
 - [hat] F16 dialect phase refactored
 - Merge branch 'code-reflection' into hat/fp16/init
 - [hat] minor cleanup
 - [hat] Rename F16.init to F16.of
 - [hat] F16 init values within the device supported

Changes: https://git.openjdk.org/babylon/pull/629/files
  Webrev: https://webrevs.openjdk.org/?repo=babylon&pr=629&range=00
  Stats: 840 lines in 19 files changed: 685 ins; 81 del; 74 mod
  Patch: https://git.openjdk.org/babylon/pull/629.diff
  Fetch: git fetch https://git.openjdk.org/babylon.git pull/629/head:pull/629

PR: https://git.openjdk.org/babylon/pull/629