[mlir][sparse] fixed inaccury in maintaining universal index

The universal index was maintained if dense indices were still
in place, and lattice points followed. However, it should only
be kept if any of those following lattice points actually
consumes the universal index. This change also fixes an
inaccuracy with a missing broadcast around vector invariant.

Reviewed By: bixia

Differential Revision: https://reviews.llvm.org/D97594