iris: don't assert on unfinished aux import in copy paths

iris: don't assert on unfinished aux import in copy paths

After a resource is created the first command using it could be a copy
command.

In iris_state we finish the import on surface/view creation but we
don't do that for copies.

v2: Move finish call to gallium entrypoints (Ken)

Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Cc: <mesa-stable@lists.freedesktop.org>
Closes: https://gitlab.freedesktop.org/mesa/mesa/-/issues/2725
Reviewed-by: Tapani Pälli <tapani.palli@intel.com> (v1)
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4657>