Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/tools/testing/selftests/sigaltstack/sas.c b/tools/testing/selftests/sigaltstack/sas.c
index 228c2ae..ad0f8df 100644
--- a/tools/testing/selftests/sigaltstack/sas.c
+++ b/tools/testing/selftests/sigaltstack/sas.c
@@ -109,6 +109,7 @@
 	int err;
 
 	ksft_print_header();
+	ksft_set_plan(3);
 
 	sigemptyset(&act.sa_mask);
 	act.sa_flags = SA_ONSTACK | SA_SIGINFO;