RFR: 8324717: Remove HotSpotJVMCICompilerFactory

[Doug Simon]

There has been no active use of `jdk.vm.ci.hotspot.HotSpotJVMCICompilerFactory.CompilationLevelAdjustment` since [JDK-8219403](https://bugs.openjdk.org/browse/JDK-8219403) effectively [disabled](https://github.com/openjdk/jdk/commit/61f35bf898d6a0f4e7b6e514821b40efd87396dc#diff-4d3a3b7e7e12e1d5b4cf3e4677d9e0de5e9df3bbf1bbfa0d8d43d12098d67dc4R302-R306) it. Since `HotSpotJVMCICompilerFactory` exists solely for `CompilationLevelAdjustment` related logic, this PR removes the whole `HotSpotJVMCICompilerFactory` class.

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Commit messages:
 - remove unsupported HotSpotJVMCICompilerFactory class

Changes: https://git.openjdk.org/jdk/pull/17570/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=17570&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8324717
  Stats: 100 lines in 2 files changed: 0 ins; 100 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/17570.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/17570/head:pull/17570

PR: https://git.openjdk.org/jdk/pull/17570