Turn mention of inexistant from_external_display() into proper doc-…

…link

wayland-client/src/lib.rs

@@ -154,11 +154,12 @@
 //! - If you need to send pointers to FFI, you can retrive the `*mut wl_proxy` pointers from the proxies by
 //! first getting the [`ObjectId`](crate::backend::ObjectId) using the [`Proxy::id()`] method, and then
 //! using the `ObjectId::as_ptr()` method.
-//! - If you need to receive pointers from FFI, you need to first create a
-//! [`Backend`](crate::backend::Backend) from the `*mut wl_display` using the `from_external_display()`
-//! method (see `wayland-backend` docs), and then make it into a [`Connection`] using
-//! [`Connection::from_backend()`]. Similarly, you can make [`ObjectId`]s from the `*mut wl_proxy` pointers
-//! using `ObjectId::from_ptr()`, and then make the proxies using [`Proxy::from_id`].
+// - If you need to receive pointers from FFI, you need to first create a
+// [`Backend`][backend::Backend] from the `*mut wl_display` using
+// [`Backend::from_external_display()`][backend::Backend::from_foreign_display()], and then
+// make it into a [`Connection`] using [`Connection::from_backend()`]. Similarly, you can make
+// [`ObjectId`]s from the `*mut wl_proxy` pointers using [`ObjectId::from_ptr()`], and then make
+// the proxies using [`Proxy::from_id()`].
 
 #![allow(clippy::needless_doctest_main)]
 #![warn(missing_docs, missing_debug_implementations)]