Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/scripts/atomic/fallbacks/read_acquire b/scripts/atomic/fallbacks/read_acquire
new file mode 100755
index 0000000..75863b5
--- /dev/null
+++ b/scripts/atomic/fallbacks/read_acquire
@@ -0,0 +1,7 @@
+cat <<EOF
+static inline ${ret}
+${atomic}_read_acquire(const ${atomic}_t *v)
+{
+	return smp_load_acquire(&(v)->counter);
+}
+EOF