Linux/EGL: prime render offload does not work, iGPU is always used

[thesourcehim]

State your operating system:

Linux Fedora 41, GTK3 frontend, OpenGL 3.2/GLES 3 with EGL

DesMuME version

git master

Issue

For some reason when EGL is used to initialize OpenGL or GLES, Intel iGPU is always used despite environment variables are set to use NVIDIA GPU. Other EGL based apps (eglgears for example) work as expected, also if desmume uses SDL for init then everything also works right.