mmc: cavium-thunderx: Add of_node_put() when breaking out of loop

In thunder_mmc_probe(), we should call of_node_put() when breaking
out of for_each_child_of_node() which has increased and decreased
the refcount during each iteration.

Fixes: 166bac38c3c5 ("mmc: cavium: Add MMC PCI driver for ThunderX SOCs")
Signed-off-by: Liang He <[e-mail]>
Acked-by: Robert Richter <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Ulf Hansson <[e-mail]>

drivers/mmc/host/cavium-thunderx.c

···
 				continue;
 
 			ret = cvm_mmc_of_slot_probe(&host->slot_pdev[i]->dev, host);
-			if (ret)
+			if (ret) {
+				of_node_put(child_node);
 				goto error;
+			}
 		}
 		i++;
 	}