tty: Add N_CAN327 line discipline ID for ELM327 based CAN driver

The actual driver will be added via the CAN tree.

Link: https://lore.kernel.org/all/20220618180134.9890-1-max@enpas.org
Link: https://lore.kernel.org/all/Yrm9Ezlw1dLmIxyS@kroah.com
Signed-off-by: Max Staudt <max@enpas.org>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

include/uapi/linux/tty.h

@@ -38,8 +38,9 @@
 #define N_NULL		27	/* Null ldisc used for error handling */
 #define N_MCTP		28	/* MCTP-over-serial */
 #define N_DEVELOPMENT	29	/* Manual out-of-tree testing */
+#define N_CAN327	30	/* ELM327 based OBD-II interfaces */
 
 /* Always the newest line discipline + 1 */
-#define NR_LDISCS	30
+#define NR_LDISCS	31
 
 #endif /* _UAPI_LINUX_TTY_H */