AR7: use correct UART port type

    PORT_AR7 has the correct TRIG flag (UART_FCR_R_TRIG_00) as well as UART_CAP_AFE
    being set. This fixes kernel console on TNETD7300 revision 0x02 and has no side
    effects on other revisions of the chip.

    Signed-off-by: Florian Fainelli <florian@openwrt.org>

--- a/arch/mips/ar7/platform.c
+++ b/arch/mips/ar7/platform.c
@@ -509,7 +509,7 @@ static int __init ar7_register_devices(v
 
 	memset(uart_port, 0, sizeof(struct uart_port) * 2);
 
-	uart_port[0].type = PORT_16550A;
+	uart_port[0].type = PORT_AR7;
 	uart_port[0].line = 0;
 	uart_port[0].irq = AR7_IRQ_UART0;
 	uart_port[0].uartclk = ar7_bus_freq() / 2;
@@ -524,7 +524,7 @@ static int __init ar7_register_devices(v
 
 	/* Only TNETD73xx have a second serial port */
 	if (ar7_has_second_uart()) {
-		uart_port[1].type = PORT_16550A;
+		uart_port[1].type = PORT_AR7;
 		uart_port[1].line = 1;
 		uart_port[1].irq = AR7_IRQ_UART1;
 		uart_port[1].uartclk = ar7_bus_freq() / 2;