eglplatform.h: Define Wayland native platform types

This is conditional on WL_EGL_PLATFORM being #defined, so application
must make sure to include wayland-egl.h before including any egl header.

include/EGL/eglplatform.h

@@ -78,6 +78,12 @@ typedef int   EGLNativeDisplayType;
 typedef void *EGLNativeWindowType;
 typedef void *EGLNativePixmapType;
 
+#elif defined(WL_EGL_PLATFORM)
+
+typedef struct wl_egl_display *EGLNativeDisplayType;
+typedef struct wl_egl_pixmap  *EGLNativePixmapType;
+typedef struct wl_egl_window  *EGLNativeWindowType;
+
 #elif defined(__unix__) || defined(__unix)
 
 #ifdef MESA_EGL_NO_X11_HEADERS