blackfin: convert to use CONFIG_SYS_I2C framework

Signed-off-by: Scott Jiang <scott.jiang.linux@gmail.com>
diff --git a/include/configs/cm-bf537u.h b/include/configs/cm-bf537u.h
index 5dffd1b..1f26457 100644
--- a/include/configs/cm-bf537u.h
+++ b/include/configs/cm-bf537u.h
@@ -120,8 +120,8 @@
 /*
  * I2C Settings
  */
+#define CONFIG_SYS_I2C
 #define CONFIG_SYS_I2C_ADI
-#define CONFIG_HARD_I2C		1
 
 
 /*