remoteproc: stm32: Call of_node_put() on iteration error

commit ccadca5 upstream.

Function of_phandle_iterator_next() calls of_node_put() on the last
device_node it iterated over, but when the loop exits prematurely it has
to be called explicitly.

Fixes: 13140de ("remoteproc: stm32: add an ST stm32_rproc driver")
Cc: stable@vger.kernel.org
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Arnaud Pouliquen <arnaud.pouliquen@foss.st.com>
Link: https://lore.kernel.org/r/20230320221826.2728078-2-mathieu.poirier@linaro.org
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/remoteproc/stm32_rproc.c

@@ -223,11 +223,13 @@ static int stm32_rproc_prepare(struct rproc *rproc)
 	while (of_phandle_iterator_next(&it) == 0) {
 		rmem = of_reserved_mem_lookup(it.node);
 		if (!rmem) {
+			of_node_put(it.node);
 			dev_err(dev, "unable to acquire memory-region\n");
 			return -EINVAL;
 		}
 
 		if (stm32_rproc_pa_to_da(rproc, rmem->base, &da) < 0) {
+			of_node_put(it.node);
 			dev_err(dev, "memory region not valid %pa\n",
 				&rmem->base);
 			return -EINVAL;
@@ -254,8 +256,10 @@ static int stm32_rproc_prepare(struct rproc *rproc)
 							   it.node->name);
 		}
 
-		if (!mem)
+		if (!mem) {
+			of_node_put(it.node);
 			return -ENOMEM;
+		}
 
 		rproc_add_carveout(rproc, mem);
 		index++;