media: imx: imx7_mipi_csis: Fix error return code in mipi_csis_async_register()

Fix to return negative error code -EINVAL from the error handling
case instead of 0, as done elsewhere in this function.

Fixes: 88fc8138 ("media: imx: imx7_mipi_csis: Reject invalid data-lanes settings")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Acked-by: Rui Miguel Silva <rmfrfs@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>