i2c: ast_i2c: Update to use standard enums for speed

Update this driver to use the new standard enums for speed.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Heiko Schocher <hs@denx.de>
diff --git a/drivers/i2c/ast_i2c.c b/drivers/i2c/ast_i2c.c
index 763183d..35dc234 100644
--- a/drivers/i2c/ast_i2c.c
+++ b/drivers/i2c/ast_i2c.c
@@ -314,7 +314,7 @@
 	divider = i2c_rate / speed;
 
 	priv->speed = speed;
-	if (speed > I2C_HIGHSPEED_RATE) {
+	if (speed > I2C_SPEED_FAST_RATE) {
 		debug("Enable High Speed\n");
 		setbits_le32(&regs->fcr, I2CD_M_HIGH_SPEED_EN
 			     | I2CD_M_SDA_DRIVE_1T_EN
diff --git a/drivers/i2c/ast_i2c.h b/drivers/i2c/ast_i2c.h
index 401e097..9287859 100644
--- a/drivers/i2c/ast_i2c.h
+++ b/drivers/i2c/ast_i2c.h
@@ -126,6 +126,4 @@
 #define I2CD_RX_DATA_SHIFT			8
 #define I2CD_RX_DATA_MASK			(0xff << I2CD_RX_DATA_SHIFT)
 
-#define I2C_HIGHSPEED_RATE    400000
-
 #endif				/* __AST_I2C_H_ */