RFR: 8294976: test/hotspot 183 test classes use ASM

[Oussama Louati]

Modified 2/180 test classes that use asm.

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Commit messages:
 - Add initialization and target methods to GenCPFullOfMH.java
 - Refactor generateCPEntryData method in GenCPFullOfMH.java
 - return finishMethodCode() method to GenFullCP.java as it's neede for other tests
 - Refactor code to return byte array in createClassInitMethod, createInitMethod, createTargetMethod, and createBootstrapMethod methods
 - Remove unnecessary whitespaces in GenFullCP.java
 - refactor code and fix some compilation errors
 - finished fst draft of conversion to classfile API
 - Refactor getBytecodeLength method in ClassWriterExt.java
 - Add support for retrieving bytecode length using ClassModel instead if MethodVisitor

Changes: https://git.openjdk.org/jdk/pull/17834/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=17834&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8294976
  Stats: 382 lines in 3 files changed: 153 ins; 128 del; 101 mod
  Patch: https://git.openjdk.org/jdk/pull/17834.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/17834/head:pull/17834

PR: https://git.openjdk.org/jdk/pull/17834