doc/go1.22: document that reflect.PtrTo is deprecated

Updates #59599.
For #61422.

Change-Id: I923be38b719a78dd983372acad93f710a53b0922
Reviewed-on: https://go-review.googlesource.com/c/go/+/548036
Reviewed-by: Keith Randall <khr@google.com>
TryBot-Bypass: Cherry Mui <cherryyz@google.com>
Reviewed-by: Keith Randall <khr@golang.org>

doc/go1.22.html

@@ -633,6 +633,12 @@ <h3 id="minor_library_changes">Minor changes to the library</h3>
       a value to zero using the language <code>==</code> operator.
     </p>
   </dd>
+  <dd>
+    <p><!-- https://go.dev/issue/59599, CL 511035 -->
+      The <a href="/pkg/reflect/#PtrTo"><code>PtrTo</code></a> function is deprecated,
+      in favor of <a href="/pkg/reflect/#PointerTo"><code>PointerTo</code></a>.
+    </p>
+  </dd>
 </dl><!-- reflect -->
 
 <dl id="runtime/metrics"><dt><a href="/pkg/runtime/metrics/">runtime/metrics</a></dt>