Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/drivers/mtd/devices/block2mtd.c b/drivers/mtd/devices/block2mtd.c
index c9e4249..410a321 100644
--- a/drivers/mtd/devices/block2mtd.c
+++ b/drivers/mtd/devices/block2mtd.c
@@ -329,8 +329,10 @@
 	switch (**endp) {
 	case 'G' :
 		result *= 1024;
+		/* fall through */
 	case 'M':
 		result *= 1024;
+		/* fall through */
 	case 'K':
 	case 'k':
 		result *= 1024;