window: make window_{create,set}_surface private

I do not think these are meant to be called by the applications
directly. Applications certainly do not have to call them.

Signed-off-by: Pekka Paalanen <ppaalanen@gmail.com>

clients/window.c

@@ -889,7 +889,7 @@ window_flush(struct window *window)
 		window_attach_surface(window);
 }
 
-void
+static void
 window_set_surface(struct window *window, cairo_surface_t *surface)
 {
 	cairo_surface_reference(surface);
@@ -928,7 +928,7 @@ window_get_display(struct window *window)
 	return window->display;
 }
 
-void
+static void
 window_create_surface(struct window *window)
 {
 	cairo_surface_t *surface;

clients/window.h

@@ -273,12 +273,6 @@ window_get_wl_shell_surface(struct window *window);
 void
 window_flush(struct window *window);
 
-void
-window_set_surface(struct window *window, cairo_surface_t *surface);
-
-void
-window_create_surface(struct window *window);
-
 enum window_buffer_type {
 	WINDOW_BUFFER_TYPE_EGL_WINDOW,
 	WINDOW_BUFFER_TYPE_SHM,