"miDebuggerPath" completely ignored when "debugServerPath" is used

Describe the bug

• OS and Version: Windows/Linux (Version does not matter)
• VS Code Version: Does not matter.
• C/C++ Extension Version: UPSTREAM (0.21.0)
• Other extensions you installed (and if the issue persists after disabling them): Does not have any influence.
• A clear and concise description of what the bug is:

When you specify a debugServerPath and a debugServerArgs, miDebuggerPath and miDebuggerArgs are completely ignored. Furthermore you HAVE to specify a miDebuggerServerAddress even tho that is not necessarily required as you can specify this via miDebuggerArgs

To Reproduce
Please include a code sample and launch.json configuration.
See the launch.jsonbelow:

{
    "version": "0.2.0",
    "configurations": [
      {
        "name": "COM Example",
        "type": "cppdbg",
        "request": "launch",
        "program": "${workspaceRoot}/target/thumbv7em-none-eabihf/debug/examples/com",
        "args": [],
        "miDebuggerServerAddress": "localhost:2331",
        "stopAtEntry": true,
        "cwd": "${workspaceRoot}",
        "environment": [],
        //"externalConsole": true,
        "linux": {
          "MIMode": "gdb"
        },
        "osx": {
          "MIMode": "gdb"
        },
        "windows": {
          "MIMode": "gdb",
          "setupCommands": [{
            "text": "load"
          }],
          //"preLaunchTask": "cargo build com",
          "debugServerPath": "C:\\Program Files (x86)\\SEGGER\\JLink_V640\\JLinkGDBServerCL.exe",
          "debugServerArgs": "-select USB -device nRF52840_xxAA -endian little -if SWD -speed 4000 -noir -LocalhostOnly",
          "miDebuggerPath": "C:\\Program Files (x86)\\GNU Tools ARM Embedded\\8 2018-q4-major\\bin\\arm-none-eabi-gdb.exe",
          "miDebuggerArgs": "-q -x debug.gdb target/thumbv7m-none-eabi/debug/examples/com",
        }
      }
    ]
  }

Steps to reproduce the behavior:

1. Use the launch.json above.

Additional context
I tried finding the source code that uses the miDebuggerPath etc, but I can't even locate the variable in this repo. So I can't even see how this extension ever uses that value. If I could, I would fix it myself, but the entire extension is really intransparent, including all the config explanations (especially the problemMatcher).

Start by tracing how the cppdbg launch configuration parses the launch.json example, searching for debugServerPath, debugServerArgs, miDebuggerPath, and miDebuggerArgs. Reproduce the configuration on Windows or Linux and determine why the debugger path and arguments are ignored. Done means both settings work with a debugServerPath without requiring miDebuggerServerAddress when the address is supplied through miDebuggerArgs.