Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/net/atm/resources.c b/net/atm/resources.c
index bada395..889349c 100644
--- a/net/atm/resources.c
+++ b/net/atm/resources.c
@@ -203,13 +203,9 @@
 	int __user *sioc_len;
 	int __user *iobuf_len;
 
-#ifndef CONFIG_COMPAT
-	compat = 0; /* Just so the compiler _knows_ */
-#endif
-
 	switch (cmd) {
 	case ATM_GETNAMES:
-		if (compat) {
+		if (IS_ENABLED(CONFIG_COMPAT) && compat) {
 #ifdef CONFIG_COMPAT
 			struct compat_atm_iobuf __user *ciobuf = arg;
 			compat_uptr_t cbuf;
@@ -253,7 +249,7 @@
 		break;
 	}
 
-	if (compat) {
+	if (IS_ENABLED(CONFIG_COMPAT) && compat) {
 #ifdef CONFIG_COMPAT
 		struct compat_atmif_sioc __user *csioc = arg;
 		compat_uptr_t carg;
@@ -417,7 +413,7 @@
 		}
 		/* fall through */
 	default:
-		if (compat) {
+		if (IS_ENABLED(CONFIG_COMPAT) && compat) {
 #ifdef CONFIG_COMPAT
 			if (!dev->ops->compat_ioctl) {
 				error = -EINVAL;