of: dynamic: changeset prop-update revert fix

When reverting an update property changeset entry that created a
property the reverse operation is a remove property and not an update.

Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Signed-off-by: Rob Herring <robh@kernel.org>
diff --git a/drivers/of/dynamic.c b/drivers/of/dynamic.c
index 75ce30d..3033fa3 100644
--- a/drivers/of/dynamic.c
+++ b/drivers/of/dynamic.c
@@ -498,6 +498,11 @@
 	case OF_RECONFIG_UPDATE_PROPERTY:
 		rce->old_prop = ce->prop;
 		rce->prop = ce->old_prop;
+		/* update was used but original property did not exist */
+		if (!rce->prop) {
+			rce->action = OF_RECONFIG_REMOVE_PROPERTY;
+			rce->prop = ce->prop;
+		}
 		break;
 	}
 }