i965: Enable GL_OES_geometry_shader on Gen8+

Gen7 can get this extension (and GL_OES_shader_io_blocks) as soon as the
rest of OpenGL ES 3.1 is enabled.

Signed-off-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Ilia Mirkin <imirkin@alum.mit.edu>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>

docs/features.txt

@@ -260,7 +260,7 @@ GLES3.2, GLSL ES 3.2:
   GL_OES_copy_image                                     DONE (all drivers)
   GL_OES_draw_buffers_indexed                           DONE (all drivers that support GL_ARB_draw_buffers_blend)
   GL_OES_draw_elements_base_vertex                      DONE (all drivers)
-  GL_OES_geometry_shader                                started (idr)
+  GL_OES_geometry_shader                                DONE (i965/gen8+)
   GL_OES_gpu_shader5                                    DONE (all drivers that support GL_ARB_gpu_shader5)
   GL_OES_primitive_bounding_box                         not started
   GL_OES_sample_shading                                 DONE (i965, nvc0, r600, radeonsi)

docs/relnotes/12.1.0.html

@@ -57,6 +57,7 @@ Note: some of the new features are only available with certain drivers.
 <li>GL_ARB_texture_stencil8 on i965/hsw</li>
 <li>OpenGL ES 3.1 on i965/hsw</li>
 <li>GL_KHR_blend_equation_advanced on i965</li>
+<li>GL_OES_geometry_shader on i965/gen8+.</li>
 </ul>
 
 <h2>Bug fixes</h2>

src/mesa/drivers/dri/i965/intel_extensions.c

@@ -398,6 +398,7 @@ intelInitExtensions(struct gl_context *ctx)
       ctx->Extensions.ARB_shader_precision = true;
       ctx->Extensions.ARB_gpu_shader_fp64 = true;
       ctx->Extensions.ARB_vertex_attrib_64bit = true;
+      ctx->Extensions.OES_geometry_shader = true;
       ctx->Extensions.OES_shader_io_blocks = true;
    }