serial: add support for the TI AR7 internal UART

This patch adds support for the TI AR7 internal UART.

Signed-off-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index 57a97e5..48766ea 100644
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -41,7 +41,8 @@
 #define PORT_XSCALE	15
 #define PORT_RM9000	16	/* PMC-Sierra RM9xxx internal UART */
 #define PORT_OCTEON	17	/* Cavium OCTEON internal UART */
-#define PORT_MAX_8250	17	/* max port ID */
+#define PORT_AR7	18	/* Texas Instruments AR7 internal UART */
+#define PORT_MAX_8250	18	/* max port ID */
 
 /*
  * ARM specific type numbers.  These are not currently guaranteed