aco: fix image load/store with lod and 1D images

aco: fix image load/store with lod and 1D images

Make sure to add the lod value if non-null as the 2nd operand.

Fixes dEQP-VK.image.load_store_lod.with_format.1d.* on all gens
except GFX9.

Fixes: 4d49a7ac737 ("aco: handle nir_intrinsic_image_deref_{load,store} with lod")
Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Reviewed-by: Daniel Schürmann <daniel@schuermann.dev>
Reviewed-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com>
Tested-by: Marge Bot <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4060>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4060>