iio: proximity: vl53l0x-i2c: Added continuous mode support

iio: proximity: vl53l0x-i2c: Added continuous mode support

The continuous mode of the sensor is enabled in the buffer_postenable.
Replaced the original irq handler with a threaded irq handler to perform
i2c reads during continuous mode.
The continuous mode is disabled by disabling the buffer.
Added a trigger for this device to be used for continuous mode.

Signed-off-by: Abhash Jha <abhashkumarjha123@gmail.com>
Link: https://patch.msgid.link/20240909101508.263085-3-abhashkumarjha123@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>