doc: document r58.1

R=adg, dsymonds
CC=golang-dev
https://golang.org/cl/4700041

doc/devel/release.html

@@ -86,6 +86,14 @@ the Go tree (and avoid writing Makefiles).
 </p>
 
 
+<h3 id="r58.minor">Minor revisions</h3>
+
+<p>r58.1 adds 
+<a href="http://code.google.com/p/go/source/detail?r=293c25943586">build</a> and
+<a href="http://code.google.com/p/go/source/detail?r=bf17e96b6582">runtime</a>
+changes to make Go run on OS X 10.7 Lion.
+</p>
+
 <h2 id="r57">r57 (released 2011/05/03)</h2>
 
 <p>