docs/features: show es3.1 compat done on r600.

This was already being reported, just missed the docs.

Reported-by: Dieter Nützel <Dieter@nuetzel-hh.de>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/docs/features.txt b/docs/features.txt
index f6aec63..eed3076 100644
--- a/docs/features.txt
+++ b/docs/features.txt
@@ -208,7 +208,7 @@
 
 GL 4.5, GLSL 4.50 -- all DONE: nvc0, radeonsi
 
-  GL_ARB_ES3_1_compatibility                            DONE (i965/hsw+)
+  GL_ARB_ES3_1_compatibility                            DONE (i965/hsw+, r600)
   GL_ARB_clip_control                                   DONE (freedreno, i965, nv50, r600, llvmpipe, softpipe, swr)
   GL_ARB_conditional_render_inverted                    DONE (freedreno, i965, nv50, r600, llvmpipe, softpipe, swr)
   GL_ARB_cull_distance                                  DONE (i965, nv50, r600, llvmpipe, softpipe, swr)