fpga: add configuration for the FPGA KUnit test suites.

Add configuration for the KUnit test suites for the core components
of the FPGA subsystem.

Signed-off-by: Marco Pagani <marpagan@redhat.com>
Acked-by: Xu Yilun <yilun.xu@intel.com>
Link: https://lore.kernel.org/r/20230718130304.87048-5-marpagan@redhat.com
Signed-off-by: Xu Yilun <yilun.xu@intel.com>