arm, imx6, i2c: add I2C4 for MX6DL

add I2C4 modul for MX6DL based boards.

Signed-off-by: Heiko Schocher <hs@denx.de>
diff --git a/arch/arm/imx-common/i2c-mxv7.c b/arch/arm/imx-common/i2c-mxv7.c
index f3a5c3f..ff72b1a 100644
--- a/arch/arm/imx-common/i2c-mxv7.c
+++ b/arch/arm/imx-common/i2c-mxv7.c
@@ -67,9 +67,12 @@
 #ifdef I2C3_BASE_ADDR
 	(void *)I2C3_BASE_ADDR,
 #endif
+#ifdef I2C4_BASE_ADDR
+	(void *)I2C4_BASE_ADDR,
+#endif
 };
 
-/* i2c_index can be from 0 - 2 */
+/* i2c_index can be from 0 - 3 */
 int setup_i2c(unsigned i2c_index, int speed, int slave_addr,
 	      struct i2c_pads_info *p)
 {