zink: mark off GL 3.1 as done in features.txt

Reviewed-by: Erik Faye-Lund <erik.faye-lund@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/7109>
diff --git a/docs/features.txt b/docs/features.txt
index 462b907..73248d7 100644
--- a/docs/features.txt
+++ b/docs/features.txt
@@ -69,17 +69,17 @@
 (*) freedreno (a2xx-a4xx), llvmpipe, softpipe, and swr have fake Multisample anti-aliasing support
 
 
-GL 3.1, GLSL 1.40 --- all DONE: freedreno, i965, nv50, nvc0, r600, radeonsi, llvmpipe, softpipe, swr, virgl, panfrost
+GL 3.1, GLSL 1.40 --- all DONE: freedreno, i965, nv50, nvc0, r600, radeonsi, llvmpipe, softpipe, swr, virgl, panfrost, zink
 
   Forward compatible context support/deprecations       DONE
-  GL_ARB_draw_instanced (Instanced drawing)             DONE (v3d, zink)
-  GL_ARB_copy_buffer (Buffer copying)                   DONE (v3d, zink)
+  GL_ARB_draw_instanced (Instanced drawing)             DONE (v3d)
+  GL_ARB_copy_buffer (Buffer copying)                   DONE (v3d)
   GL_NV_primitive_restart (Primitive restart)           DONE ()
-  16 vertex texture image units                         DONE (zink)
-  GL_ARB_texture_buffer_object (Texture buffer objs)    DONE (zink)
-  GL_ARB_texture_rectangle (Rectangular textures)       DONE (v3d, zink)
-  GL_ARB_uniform_buffer_object (Uniform buffer objs)    DONE (v3d, zink)
-  GL_EXT_texture_snorm (Signed normalized textures)     DONE (v3d, zink)
+  16 vertex texture image units                         DONE ()
+  GL_ARB_texture_buffer_object (Texture buffer objs)    DONE ()
+  GL_ARB_texture_rectangle (Rectangular textures)       DONE (v3d)
+  GL_ARB_uniform_buffer_object (Uniform buffer objs)    DONE (v3d)
+  GL_EXT_texture_snorm (Signed normalized textures)     DONE (v3d)
 
 
 GL 3.2, GLSL 1.50 --- all DONE: i965, nv50, nvc0, r600, radeonsi, llvmpipe, softpipe, swr, virgl