i2c: fsl: Use dev_read_addr

Since bus translations are now fully supported, use a plain
"dev_read_addr" to get the device address from the device tree.

Signed-off-by: Mario Six <mario.six@gdsys.cc>
diff --git a/drivers/i2c/fsl_i2c.c b/drivers/i2c/fsl_i2c.c
index cb0f5ea..ad8eea4 100644
--- a/drivers/i2c/fsl_i2c.c
+++ b/drivers/i2c/fsl_i2c.c
@@ -573,11 +573,8 @@
 static int fsl_i2c_ofdata_to_platdata(struct udevice *bus)
 {
 	struct fsl_i2c_dev *dev = dev_get_priv(bus);
-	fdt_addr_t addr;
-
-	addr = dev_read_u32_default(bus, "reg", -1);
 
-	dev->base = map_sysmem(CONFIG_SYS_IMMR + addr, sizeof(struct fsl_i2c_base));
+	dev->base = map_sysmem(dev_read_addr(bus), sizeof(struct fsl_i2c_base));
 
 	if (!dev->base)
 		return -ENOMEM;