BugLink: https://bugs.launchpad.net/bugs/1818813

[ Upstream commit 6ae16dfb ]

In lenovo_probe_tpkbd(), the function of_led_classdev_register() could
return an error value that is unchecked. The fix adds these checks.
Signed-off-by: Aditya Pakki <pakki001@umn.edu>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Juerg Haefliger <juergh@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>