Can't build totalcross VM for arm32v7

Describe the bug

Build the totalcross VM for arm32v7 is not possible.

Devices:

Please complete the following information:

• Distributor ID: Ubuntu Description: Ubuntu 18.04.5 LTS
• cmake version 3.10.2
• Docker version 20.10.8, build 3967b7d
• TotalCross Version: latest from master branch
• Architecture: arm32v7

To Reproduce

git clone https://github.com/TotalCross/totalcross.git
cd  totalcross/TotalCrossVM/docker/arm32v7
sudo ./build-docker.sh

 => ERROR [build 7/7] RUN cmake /sources -G Ninja && ninja                                                                                                              0.4s
------                                                                                                                                                                       
 > [build 7/7] RUN cmake /sources -G Ninja && ninja:                                                                                                                         
#11 0.345 CMake Error: The source directory "/sources" does not appear to contain CMakeLists.txt.
#11 0.345 Specify --help for usage, or press the help button on the CMake GUI.
------
Dockerfile:70
--------------------
  68 |     COPY . /sources
  69 |     
  70 | >>> RUN cmake /sources -G Ninja && ninja
  71 |     
  72 |     CMD ["/bin/bash", "-c", "make", "-j$(($(nproc) + 2))", "-f", "${BUILD_FOLDER}/Makefile"]
--------------------
error: failed to solve: process "/bin/sh -c cmake /sources -G Ninja && ninja" did not complete successfully: exit code: 1

Hello @ubx.

Do you have your arm32v7 device avaliable? Currently we just added a new topic in the page about building the VM for Linux natively using CMake, this way you don't need to rely on Docker to build it. Being the native method on the other hand, means that you'll need to build it on the arm32v7 device, not on your Ubuntu desktop.

We would appreciate feedback on the instructions provided, as well as if it build was successful and if the built-natively VM is working properly.

If, however, building TotalCrossVM natively on your arm device is not an option for you, we humbly request your patience as fixes for the docker scripts are currently WIP and should be out soon.