RFR: 8373134: C2: Min/Max users of Min/Max uses should be enqueued for GVN [v8]

[Galder Zamarreño]

> Min/Max users of Min/Max uses need to be enqueued respectively to the GVN worklist to see if further optimizations can be applied. Without this, there are cases where additional potential ideal/identity optimizations are not applied. I need this fix to test min/max reassociation implementation with IR tests reliably.
> 
> Aside from the fix itself, I've refactored `MaxNode` to `MinMaxNode` and added a `is_MinMax` node query to simplify the fix.
> 
> I have also removed the Min/Max exceptions in `PhaseIterGVN::verify_Identity_for` since this fix fixes `compiler/codegen/TestBooleanVect.java` with `-XX:VerifyIterativeGVN=1110`.
> 
> To test this I've created a template framework test that validates the fix. I have tested with all Min/Max combinations including Float16, which I've verified with Intel SDE. Float16 does not use `Argument.NUMBER_42` because there's no support for it yet, see [JDK-8373977](https://bugs.openjdk.org/browse/JDK-8373977).
> 
> During development I noticed that the test only failed when the test had `b, a` parameters in that order, so I added tests for both cases as `a, b` and `b, a` so that all possible orders are covered and they don't slip in the future.
> 
> I've run tier1-3 tests on linux/x64 successfully.

Galder Zamarreño has updated the pull request incrementally with two additional commits since the last revision:

 - Update test/hotspot/jtreg/compiler/igvn/TestMinMaxIdentity.java
   
   Co-authored-by: Emanuel Peter <emanuel.peter at oracle.com>
 - Fix style

-------------

Changes:
  - all: https://git.openjdk.org/jdk/pull/28895/files
  - new: https://git.openjdk.org/jdk/pull/28895/files/fe71e03f..2c0b0e43

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=28895&range=07
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=28895&range=06-07

  Stats: 7 lines in 2 files changed: 0 ins; 0 del; 7 mod
  Patch: https://git.openjdk.org/jdk/pull/28895.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/28895/head:pull/28895

PR: https://git.openjdk.org/jdk/pull/28895