dm: core: Add ofnode_read_resource()

We sometimes need to read a resource from an arbitrary node. In any case
for consistency we should not put the live-tree switching code in
a dev_read_...() function. Update this to suit.

Signed-off-by: Simon Glass <sjg@chromium.org>
Tested-by: Marcel Ziswiler <marcel.ziswiler@toradex.com>
Tested-on: Beaver, Jetson-TK1
Tested-by: Stephen Warren <swarren@nvidia.com>
diff --git a/drivers/core/read_extra.c b/drivers/core/read_extra.c
index a6d2f34..e94648f 100644
--- a/drivers/core/read_extra.c
+++ b/drivers/core/read_extra.c
@@ -11,27 +11,4 @@
 #include <dm/read.h>
 #include <linux/ioport.h>
 
-int dev_read_resource(struct udevice *dev, uint index, struct resource *res)
-{
-	ofnode node = dev_ofnode(dev);
-
-#ifdef CONFIG_OF_LIVE
-	if (ofnode_is_np(node)) {
-		return of_address_to_resource(ofnode_to_np(node), index, res);
-	} else
-#endif
-		{
-		struct fdt_resource fres;
-		int ret;
-
-		ret = fdt_get_resource(gd->fdt_blob, ofnode_to_offset(node),
-				       "reg", index, &fres);
-		if (ret < 0)
-			return -EINVAL;
-		memset(res, '\0', sizeof(*res));
-		res->start = fres.start;
-		res->end = fres.end;
-
-		return 0;
-	}
-}
+/* This file can hold non-inlined dev_read_...() functions */