board: hsdk: add 2 cores configuration for test

add 2 cores configuration for
* who want to use 2 cores
* sanitycheck tests, as we found there are
  difference between 2 cores and 4 cores, see
  report in issue #26794

Signed-off-by: Wayne Ren <wei.ren@synopsys.com>
Signed-off-by: Watson Zeng <zhiwei@synopsys.com>