dm: core: Add logging for DM_SEQ_ALIAS

It is sometimes helpful to see which sequence is assigned to a device.
Add debugging info for that.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/core/device.c b/drivers/core/device.c
index 9f14007..29668f6 100644
--- a/drivers/core/device.c
+++ b/drivers/core/device.c
@@ -87,8 +87,10 @@
 		if (CONFIG_IS_ENABLED(OF_CONTROL) &&
 		    !CONFIG_IS_ENABLED(OF_PLATDATA)) {
 			if (uc->uc_drv->name && ofnode_valid(node)) {
-				if (!dev_read_alias_seq(dev, &dev->seq_))
+				if (!dev_read_alias_seq(dev, &dev->seq_)) {
 					auto_seq = false;
+					log_debug("   - seq=%d\n", dev->seq_);
+					}
 			}
 		}
 	}