opengl: Support NV12 textures on GPUs with only 2 texture units

src/render/opengl/SDL_render_gl.c

@@ -1919,6 +1919,10 @@ GL_CreateRenderer(SDL_Window * window, Uint32 flags)
     if (data->shaders && data->num_texture_units >= 3) {
         renderer->info.texture_formats[renderer->info.num_texture_formats++] = SDL_PIXELFORMAT_YV12;
         renderer->info.texture_formats[renderer->info.num_texture_formats++] = SDL_PIXELFORMAT_IYUV;
+    }
+
+    /* We support NV12 textures using 2 textures and a shader */
+    if (data->shaders && data->num_texture_units >= 2) {
         renderer->info.texture_formats[renderer->info.num_texture_formats++] = SDL_PIXELFORMAT_NV12;
         renderer->info.texture_formats[renderer->info.num_texture_formats++] = SDL_PIXELFORMAT_NV21;
     }