Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/include/uapi/linux/serio.h b/include/uapi/linux/serio.h
index a0cac1d..50e9919 100644
--- a/include/uapi/linux/serio.h
+++ b/include/uapi/linux/serio.h
@@ -82,5 +82,6 @@
 #define SERIO_EGALAX	0x3f
 #define SERIO_PULSE8_CEC	0x40
 #define SERIO_RAINSHADOW_CEC	0x41
+#define SERIO_FSIA6B	0x42
 
 #endif /* _UAPI_SERIO_H */