app/internal/egl: don't exit if EGL dlls fails to load

We want a useful error instead of a hard exit for headless windows.

Signed-off-by: Elias Naur <mail@eliasnaur.com>

app/internal/egl/egl_unix.go

@@ -26,6 +26,10 @@ type (
 	NativeWindowType  = C.EGLNativeWindowType
 )
 
+func loadEGL() error {
+	return nil
+}
+
 func eglChooseConfig(disp _EGLDisplay, attribs []_EGLint) (_EGLConfig, bool) {
 	var cfg C.EGLConfig
 	var ncfg C.EGLint