uart8250io: Unify calls with generic UART

Change-Id: I6d56648e56f2177e1d5332497321e718df18300c
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: http://review.coreboot.org/5234
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>

src/cpu/x86/smm/smiutil.c

@@ -45,7 +45,7 @@ void console_tx_byte(unsigned char byte)
 		uart8250_mem_tx_byte(serial8250mem_base_address, byte);
 #endif
 #if CONFIG_CONSOLE_SERIAL8250
-	uart8250_tx_byte(CONFIG_TTYS0_BASE, byte);
+	uart_tx_byte(byte);
 #endif
 }