libnvdimm: Replace namespace_match() with device_find_child_by_name()

Simplify nd_namespace_store() implementation by
using device_find_child_by_name().

Reviewed-by: Alison Schofield <[e-mail]>
Reviewed-by: Jonathan Cameron <[e-mail]>
Signed-off-by: Zijun Hu <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/nvdimm/claim.c

···
 	return claimed;
 }
 
-static int namespace_match(struct device *dev, void *data)
-{
-	char *name = data;
-
-	return strcmp(name, dev_name(dev)) == 0;
-}
-
 static bool is_idle(struct device *dev, struct nd_namespace_common *ndns)
 {
 	struct nd_region *nd_region = to_nd_region(dev->parent);
···
 		goto out;
 	}
 
-	found = device_find_child(dev->parent, name, namespace_match);
+	found = device_find_child_by_name(dev->parent, name);
 	if (!found) {
 		dev_dbg(dev, "'%s' not found under %s\n", name,
 				dev_name(dev->parent));