coresight: Fix ref leak when of_coresight_parse_endpoint() fails

[ Upstream commit 7fcb9cb2fe47294e16067c3cfd25332c8662a115 ]

of_graph_get_next_endpoint() releases the reference to the previous
endpoint on each iteration, but when parsing fails the loop exits
early meaning the last reference is never dropped.

Fix it by dropping the refcount in the exit condition.

Fixes: d375b356e6 ("coresight: Fix support for sparsely populated ports")
Signed-off-by: James Clark <james.clark@arm.com>
Reported-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20240529133626.90080-1-james.clark@arm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>

drivers/hwtracing/coresight/coresight-platform.c

@@ -323,8 +323,10 @@ static int of_get_coresight_platform_data(struct device *dev,
 			continue;
 
 		ret = of_coresight_parse_endpoint(dev, ep, pdata);
-		if (ret)
+		if (ret) {
+			of_node_put(ep);
 			return ret;
+		}
 	}
 
 	return 0;