iio: common: scmi_sensors: Drop duplicate setting of iio_dev.dev.parent

This is already set to the same value in devm_iio_device_alloc()

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Jyoti Bhayana <jbhayana@google.com>
Reviewed-by: Alexandru Ardelean <ardeleanalex@gmail.com>
Link: https://lore.kernel.org/r/20210426170251.351957-9-jic23@kernel.org