devtmpfs: remove return value of devtmpfs_delete_node()

The only caller of device_del() does not check the return value. And
there's nothing we can do when cleaning things up on a remove path.
Let's make it a void function.

Signed-off-by: Longlong Xia <xialonglong1@huawei.com>
Link: https://lore.kernel.org/r/20230210095444.4067307-4-xialonglong1@huawei.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>