kfdtest: Add core test category

This will faciliate ASIC bringup, including under simulation environment.

Change-Id: Ie027a77a2498cba739fea51f404d9843ce8dbeae
Signed-off-by: Yong Zhao <Yong.Zhao@amd.com>

tests/kfdtest/scripts/run_kfdtest.sh

@@ -75,6 +75,7 @@ getFilter() {
         vg12 ) FILTER="--gtest_filter=$VEGA12_TESTS_BLACKLIST" ;;
         vg20 ) FILTER="--gtest_filter=$VEGA20_TESTS_BLACKLIST" ;;
         rv ) FILTER="--gtest_filter=$RAVEN_TESTS_BLACKLIST" ;;
+	core ) FILTER="--gtest_filter=$CORE_TESTS" ;;
         all ) FILTER="" ;;
         *) die "Unsupported platform $PLATFORM or node $NODE. Exiting" ;;
     esac