topology2: merge multi-core test into nocodec topology

The multi-core topology was created since multi-core feature had a few
bugs at that time so it was for validation test. Now this feature works
fine so merge it into nocodec topology then it will be tested by
github CI. And we don't need to maintain a dedicated multi-core topology.

Signed-off-by: Rander Wang <rander.wang@intel.com>

Author: RanderWang