Blackfin: blackstamp: convert eth/flash swap logic to gpio framework

Rather than bang MMRs directly, use the new portmux framework to handle
the details.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
diff --git a/board/blackstamp/blackstamp.c b/board/blackstamp/blackstamp.c
index 6355c10..06d004a 100644
--- a/board/blackstamp/blackstamp.c
+++ b/board/blackstamp/blackstamp.c
@@ -13,7 +13,7 @@
 
 #include <common.h>
 #include <netdev.h>
-#include <asm/io.h>
+#include <asm/gpio.h>
 
 DECLARE_GLOBAL_DATA_PTR;
 
@@ -27,14 +27,8 @@
 #ifdef SHARED_RESOURCES
 void swap_to(int device_id)
 {
-	bfin_write_FIO_DIR(bfin_read_FIO_DIR() | PF0);
-	SSYNC();
-	if (device_id == ETHERNET)
-		bfin_write_FIO_FLAG_S(PF0);
-	else if (device_id == FLASH)
-		bfin_write_FIO_FLAG_C(PF0);
-	else
-		printf("Unknown device to switch\n");
+	gpio_request(GPIO_PF0, "eth_flash_swap");
+	gpio_direction_output(GPIO_PF0, device_id == ETHERNET);
 	SSYNC();
 }
 #endif