commit 7151449f upstream.

If client have not provided the mask base register then do not
write into the mask register.
Signed-off-by: NLaxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: NJinyoung Park <jinyoungp@nvidia.com>
Signed-off-by: NVenkat Reddy Talla <vreddytalla@nvidia.com>
Signed-off-by: NMark Zhang <markz@nvidia.com>
Signed-off-by: NMark Brown <broonie@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>