nvmem: layouts: sl28vpd: fix device_node reference leak in error path

sl28vpd_add_cells() takes a reference on the child node via
of_get_child_by_name() for each entry and passes it to
nvmem_add_one_cell() as info.np. On success the created cell entry
adopts that reference and releases it later via of_node_put() when the
entry is torn down; nvmem_add_one_cell() does not take its own
reference. On failure it does not consume the reference either, so the
caller still owns it, but the error path only puts layout_np before
returning, leaking the child node reference.

Put info.np on the error path as well. of_node_put(NULL) is a no-op, so
this is safe even when of_get_child_by_name() returned NULL.

Fixes: d9fae023fe ("nvmem: layouts: sl28vpd: Add new layout driver")
Signed-off-by: Leo Cheng <leo-cheng@vip.qq.com>
Reviewed-by: Michael Walle <mwalle@kernel.org>
Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Srinivas Kandagatla <srini@kernel.org>
Link: https://patch.msgid.link/20261002101329.1084348-3-srini@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/nvmem/layouts/sl28vpd.c

@@ -126,6 +126,7 @@ static int sl28vpd_add_cells(struct nvmem_layout *layout)
 
 		ret = nvmem_add_one_cell(nvmem, &info);
 		if (ret) {
+			of_node_put(info.np);
 			of_node_put(layout_np);
 			return ret;
 		}