docs: mark off GL_ARB_shader_clock for zink

Reviewed-by: Adam Jackson <ajax@redhat.com>
Part-of: <!10521>

docs/features.txt

@@ -309,7 +309,7 @@ Khronos, ARB, and OES extensions that are not part of any OpenGL or OpenGL ES ve
   GL_ARB_sample_locations                               DONE (nvc0)
   GL_ARB_seamless_cubemap_per_texture                   DONE (etnaviv/SEAMLESS_CUBE_MAP, freedreno, i965, nvc0, r600, radeonsi, softpipe, swr, virgl)
   GL_ARB_shader_ballot                                  DONE (i965/gen8+, nvc0, radeonsi)
-  GL_ARB_shader_clock                                   DONE (i965/gen7+, nv50, nvc0, r600, radeonsi, virgl)
+  GL_ARB_shader_clock                                   DONE (i965/gen7+, nv50, nvc0, r600, radeonsi, virgl, zink)
   GL_ARB_shader_stencil_export                          DONE (i965/gen9+, r600, radeonsi, softpipe, llvmpipe, swr, virgl, panfrost, zink)
   GL_ARB_shader_viewport_layer_array                    DONE (i965/gen6+, nvc0, radeonsi, zink)
   GL_ARB_shading_language_include                       DONE

docs/relnotes/new_features.txt

-zink supports GL_ARB_texture_filter_minmax
+zink supports GL_ARB_texture_filter_minmax, GL_ARB_shader_clock
 VK_EXT_provoking_vertex on RADV.