RFR: 8290154: [JVMCI] partially implement JVMCI for RISC-V [v11]

[Sacha Coppey]

> This patch adds a partial JVMCI implementation for RISC-V, to allow using the GraalVM Native Image RISC-V LLVM backend, which does not use JVMCI for code emission.
> It creates the jdk.vm.ci.riscv64 and jdk.vm.ci.hotspot.riscv64 packages, as well as implements a part of jvmciCodeInstaller_riscv64.cpp. To check for correctness, it enables JVMCI code installation tests on RISC-V. More testing is performed in Native Image.

Sacha Coppey has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains ten commits:

 - Remove noinline attribute by fixing sign extended value
 - Remove vector registers from get_hotspot_reg
 - Add a comments for the change in deoptimization.hpp
 - Fix error when emitting LUI and removed vector registers
 - Ensure all JVMCI tests pass on RISC-V
 - Add space in switch
 - Avoid using set_destination when call is not jal
 - Use nativeInstruction_at instead of nativeCall_at to avoid wrongly initializating a call
 - 8290154: [JVMCI] Implement JVMCI for RISC-V

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

Changes: https://git.openjdk.org/jdk/pull/9587/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=9587&range=10
  Stats: 1723 lines in 20 files changed: 1701 ins; 0 del; 22 mod
  Patch: https://git.openjdk.org/jdk/pull/9587.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/9587/head:pull/9587

PR: https://git.openjdk.org/jdk/pull/9587