[lldb] [llvm] [lldb] Support disassembling RISC-V proprietary instructions (PR #145793)

[via llvm-commits]

tedwoodward wrote:

@DavidSpickett @jasonmolenda I uploaded a new change. It has:

- Use the exe_ctx version of python command, and HandleCommand
- Set a variable max_byte_width, and use that instead if "max_opcode_byte_size * 3 + 1" in 3 different places
- Split up RISCVPrettyPrinter comment, putting a comment line for each if branch explaining what it does
- Added an x86 disassemble -b test
- Added a simple filter and a risc-v disassemble -b test that loads fdis with the simple filter
- Added 2 lines of release notes to llvm/docs/ReleaseNotes.md

https://github.com/llvm/llvm-project/pull/145793