nir/lower-atomics-to-ssbo: remove atomic_uint arrays too

nir/lower-atomics-to-ssbo: remove atomic_uint arrays too

Maybe there is a better way to do this.  But by the time we get to
assigning uniform locs, we want the atomic_uint's to all be gone,
otherwise we assert in st_glsl_attrib_type_size().

Signed-off-by: Rob Clark <robdclark@gmail.com>