Note that you shouldn’t need to link against libEGL.so since GLFW dynamically does this itself in _glfwInitEGL() (this is called internally when you set the context creation hint to GLFW_EGL_CONTEXT_API ):
For reference purposes for an OpenGL ES example take a look at GLFW’s triangle-opengles.c.
Beyond this I don’t think I can provide much help as I haven’t got any experience with Angle on your platform.