perf: Allow printing to arbritrary fds

src/systemcmds/perf/perf.c

@@ -73,7 +73,7 @@ int perf_main(int argc, char *argv[])
 		return -1;
 	}
 
-	perf_print_all();
+	perf_print_all(0 /* stdout */);
 	fflush(stdout);
 	return 0;
 }

src/systemcmds/tests/tests_main.c

@@ -235,7 +235,7 @@ test_perf(int argc, char *argv[])
 	printf("perf: expect count of 1\n");
 	perf_print_counter(ec);
 	printf("perf: expect at least two counters\n");
-	perf_print_all();
+	perf_print_all(0);
 
 	perf_free(cc);
 	perf_free(ec);