i2c: ocores: Fix -Wint-to-pointer-cast warning

The following warning is seen in ocores_i2c.c in a 32-bit build:

  warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]

Change to use dev_read_addr_ptr().

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Leo Yu-Chi Liang <ycliang@andestech.com>
diff --git a/drivers/i2c/ocores_i2c.c b/drivers/i2c/ocores_i2c.c
index f129ec3..3b19ba7 100644
--- a/drivers/i2c/ocores_i2c.c
+++ b/drivers/i2c/ocores_i2c.c
@@ -516,7 +516,7 @@
 	u32 clock_frequency_khz;
 	int ret;
 
-	bus->base = (void __iomem *)devfdt_get_addr(dev);
+	bus->base = dev_read_addr_ptr(dev);
 
 	if (dev_read_u32(dev, "reg-shift", &bus->reg_shift)) {
 		/* no 'reg-shift', check for deprecated 'regstep' */