iio: light: vcnl4000: Check type with switch case

Check IIO_PROXIMITY  with switch case in order to make it easier
to add further types like light.
Add check for IIO_EV_INFO_VALUE for writing rising or falling events.

Signed-off-by: Astrid Rost <astrid.rost@axis.com>
Link: https://lore.kernel.org/r/20230613135025.2596641-4-astrid.rost@axis.com


Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>