fix mode option in gen-flamegraphs.sh

gen-flamegraphs.sh

@@ -14,7 +14,7 @@ do
 	mode_args='';
 	[[ "$mode" = "direct" ]] && mode_args='--direct';
 	perf_out="${DATA_DIR}"/open-bench-${mode}.data
-	${PERF_RECORD} "${perf_out}" ${OPEN_BENCH} $mode "${DIR}"
+	${PERF_RECORD} "${perf_out}" ${OPEN_BENCH} ${mode_args} "${DIR}"
 	sudo chmod a+r "${perf_out}"
 	tools/generate-flamegraph.sh "${perf_out}"
 done