[SERIAL] Make port->ops constant

No one should write to the port->ops structure, so make it constant.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index f3af477..b74ff34 100644
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -257,7 +257,7 @@
 	unsigned int		mctrl;			/* current modem ctrl settings */
 	unsigned int		timeout;		/* character-based timeout */
 	unsigned int		type;			/* port type */
-	struct uart_ops		*ops;
+	const struct uart_ops	*ops;
 	unsigned int		custom_divisor;
 	unsigned int		line;			/* port index */
 	unsigned long		mapbase;		/* for ioremap */