Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/microblaze/kernel/setup.c b/arch/microblaze/kernel/setup.c
index bbd6968..522a0c5 100644
--- a/arch/microblaze/kernel/setup.c
+++ b/arch/microblaze/kernel/setup.c
@@ -192,23 +192,14 @@
 static int microblaze_debugfs_init(void)
 {
 	of_debugfs_root = debugfs_create_dir("microblaze", NULL);
-
-	return of_debugfs_root == NULL;
+	return 0;
 }
 arch_initcall(microblaze_debugfs_init);
 
 # ifdef CONFIG_MMU
 static int __init debugfs_tlb(void)
 {
-	struct dentry *d;
-
-	if (!of_debugfs_root)
-		return -ENODEV;
-
-	d = debugfs_create_u32("tlb_skip", S_IRUGO, of_debugfs_root, &tlb_skip);
-	if (!d)
-		return -ENOMEM;
-
+	debugfs_create_u32("tlb_skip", S_IRUGO, of_debugfs_root, &tlb_skip);
 	return 0;
 }
 device_initcall(debugfs_tlb);