st/mesa: disable per-context seamless cubemap when using texture handles

st/mesa: disable per-context seamless cubemap when using texture handles

The ARB_bindless_texture spec say:

   "If ARB_seamless_cubemap (or OpenGL 4.0, which includes it) is
    supported, the per-context seamless cubemap enable is ignored
    and treated as disabled when using texture handles."

   "If AMD_seamless_cubemap_per_texture is supported, the seamless
    cube map texture parameter of the underlying texture does apply
    when texture handles are used."

The per-context seamless cubemap flag should only be enabled for
bound textures/samplers.

Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Reviewed-by: Marek Olšák <marek.olsak@amd.com>
Reviewed-by: Nicolai Hähnle <nicolai.haehnle@amd.com>