serial: fix port type conflict between NS16550A & U6_16550A

Bug seen by Dr. David Alan Gilbert with sparse
Signed-off-by: Philippe Langlais <philippe.langlais@stericsson.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

include/linux/serial.h

@@ -77,8 +77,7 @@ struct serial_struct {
 #define PORT_16654	11
 #define PORT_16850	12
 #define PORT_RSA	13	/* RSA-DV II/S card */
-#define PORT_U6_16550A	14
-#define PORT_MAX	14
+#define PORT_MAX	13
 
 #define SERIAL_IO_PORT	0
 #define SERIAL_IO_HUB6	1

include/linux/serial_core.h

@@ -44,7 +44,8 @@
 #define PORT_RM9000	16	/* PMC-Sierra RM9xxx internal UART */
 #define PORT_OCTEON	17	/* Cavium OCTEON internal UART */
 #define PORT_AR7	18	/* Texas Instruments AR7 internal UART */
-#define PORT_MAX_8250	18	/* max port ID */
+#define PORT_U6_16550A	19	/* ST-Ericsson U6xxx internal UART */
+#define PORT_MAX_8250	19	/* max port ID */
 
 /*
  * ARM specific type numbers.  These are not currently guaranteed