superio/ite/it8716f: Rewrite from hardcoded base addr

Following the same reasoning as:
HASHHERE superio/ite/it8721f: Rewrite from hardcoded base addr
Removing hard coded magics and expose sio pnp api in romstage.

Change-Id: I27433cb1a84b3641a6110ecf6bd5021e00769aba
Signed-off-by: Edward O'Callaghan <eocallaghan@alterapraxis.com>
Reviewed-on: http://review.coreboot.org/5565
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <patrick@georgi-clan.de>
diff --git a/src/mainboard/gigabyte/ga_2761gxdk/romstage.c b/src/mainboard/gigabyte/ga_2761gxdk/romstage.c
index 4d215ae..86158c8 100644
--- a/src/mainboard/gigabyte/ga_2761gxdk/romstage.c
+++ b/src/mainboard/gigabyte/ga_2761gxdk/romstage.c
@@ -38,14 +38,14 @@
 #include "lib/delay.c"
 #include "cpu/x86/lapic.h"
 #include "northbridge/amd/amdk8/reset_test.c"
-#include "superio/ite/it8716f/early_serial.c"
-#include "superio/ite/it8716f/early_init.c"
+#include <superio/ite/it8716f/it8716f.h>
 #include "cpu/x86/bist.h"
 #include "northbridge/amd/amdk8/debug.c"
 #include "northbridge/amd/amdk8/setup_resource_map.c"
 #include "southbridge/sis/sis966/early_ctrl.c"
 
 #define SERIAL_DEV PNP_DEV(0x2e, IT8716F_SP1)
+#define CLKIN_DEV PNP_DEV(0x2e, IT8716F_GPIO)
 
 static void memreset(int controllers, const struct mem_controller *ctrl) { }
 static void activate_spd_rom(const struct mem_controller *ctrl) { }
@@ -125,10 +125,8 @@
         if (bist == 0)
 		bsp_apicid = init_cpus(cpu_init_detectedx, sysinfo);
 
-	pnp_enter_ext_func_mode(SERIAL_DEV);
-        pnp_write_config(SERIAL_DEV, 0x23, 0);
- 	it8716f_enable_dev(SERIAL_DEV, CONFIG_TTYS0_BASE);
-	pnp_exit_ext_func_mode(SERIAL_DEV);
+	it8716f_conf_clkin(CLKIN_DEV, IT8716F_UART_CLK_PREDIVIDE_48);
+	it8716f_enable_serial(SERIAL_DEV, CONFIG_TTYS0_BASE);
 
         setup_mb_resource_map();