rng: rproc_rng200: Use dev_remap_addr()

Use dev_remap_addr() which supports both live device tree and flat DT
backends, avoiding direct dependency on devfdt_* helpers.

And only mapping sizeof(void *) is wrong, RNG_FIFO_COUNT_OFFSET(0x24) is
accessed in this driver. So dev_remap_addr() could also fix the mapping
size.

No functional changes.

Signed-off-by: Peng Fan <peng.fan@nxp.com>

drivers/rng/iproc_rng200.c

@@ -155,7 +155,7 @@ static int iproc_rng200_of_to_plat(struct udevice *dev)
 {
 	struct iproc_rng200_plat *pdata = dev_get_plat(dev);
 
-	pdata->base = devfdt_map_physmem(dev, sizeof(void *));
+	pdata->base = dev_remap_addr(dev);
 	if (!pdata->base)
 		return -ENODEV;