Bug Report: Missing `-lopengl32` in MinGW build on Windows (MSYS2)

[EUNA6758]

📌 Bug Report: Missing -lopengl32 in MinGW build on Windows (MSYS2)

Description
When building MRtrix3 on Windows using MSYS2 + MinGW-w64 (mingw64.exe shell), the build fails at the linking stage of mrview.exe with undefined references to __imp_wglGetProcAddress.

This happens because the -lopengl32 linker flag is not automatically included by the ./configure script under Windows/MinGW environments.

Steps to Reproduce

1. Install MSYS2 and open mingw64.exe shell

2. Install dependencies:

   pacman -S git python pkg-config mingw-w64-x86_64-gcc mingw-w64-x86_64-eigen3 mingw-w64-x86_64-qt5 mingw-w64-x86_64-fftw mingw-w64-x86_64-libtiff mingw-w64-x86_64-libpng

3. Clone MRtrix3:

   git clone https://github.com/MRtrix3/mrtrix3.git
   cd mrtrix3
   ./configure
   ./build

4. Observe the following error during mrview.exe build:

   undefined reference to `__imp_wglGetProcAddress`
   

System Info

• OS: Windows 11 x64
• Build environment: MSYS2 MinGW-w64 (mingw64.exe)
• MRtrix3 commit: [insert SHA or date]
• Qt: 5.15.16
• GCC: 15.1.0 (MSYS2)
• OpenGL: via Qt, but needs explicit -lopengl32