fix glut/freeglut links

docs/download.html

@@ -32,10 +32,10 @@ Mesa is distributed in several parts:
 </li>
 <li><b>MesaDemos-x.y.z</b> - OpenGL demonstration and test programs.
     Most of the programs require GLUT (either the
-    <a href="http://www.opengl.org/resources/libraries/glut.html"
+    <a href="http://www.opengl.org/resources/libraries/glut"
     target="_parent">original GLUT by Mark Kilgard</a> or
     <a href="http://freeglut.sourceforge.net" target="_parent">freeglut</a> or
-    <a href="http://freeglut.sourceforge.net" target="_parent">OpenGLUT</a>).
+    <a href="http://openglut.sourceforge.net" target="_parent">OpenGLUT</a>).
 </li>
 <li><b>MesaGLUT-x.y.z</b> - Mark Kilgard's GLUT, easily compiled and used
     with Mesa.  Plus, other implementation of GLUT for DOS, OS/2, BeOS, etc.