docs/features: Add missing Panfrost extensions + GL_ARB_internalformat_query + GL_ARB_texture_stencil8 + GL_ARB_stencil_texturing + GL_ARB_compute_shader + GL_ARB_shader_storage_buffer_object Signed-off-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com> Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6516>