mesa: remove GL_SGI_texture_color_table support

It was only implemented in the swrast driver and probably not used by
any applications.  A modern app would use a dependent/chained texture
lookup in the fragment shader.
diff --git a/docs/relnotes-7.11.html b/docs/relnotes-7.11.html
index 4b1730b..277339b 100644
--- a/docs/relnotes-7.11.html
+++ b/docs/relnotes-7.11.html
@@ -53,6 +53,8 @@
 <ul>
 <li>The Windows MSVC project files have been removed.  They haven't been maintained
 in quite a while.  Building with SCons is an alterantive.
+<li>Removed GL_SGI_texture_color_table support from swrast driver - the only
+driver that implemented it.
 </ul>