CN0569 undo workaround

[adrimbarean]

Undo workaround in CN0569 when UART IRQ changes support the intended operation.

Changes have to be done in main class as well as in examples.

[adrimbarean]

Workaround locations:

• https://github.com/analogdevicesinc/pyadi-iio/blob/master/examples/cn0569/adpd2140_gesture_sensor.py#L72
• https://github.com/analogdevicesinc/pyadi-iio/blob/master/examples/cn0569/adpd2140_gesture_sensor.py#L274
• https://github.com/analogdevicesinc/pyadi-iio/blob/master/examples/cn0569/cn0569_theremin_module.py#L99

The nature of the workaround is the following: data could not be written to the driver because the application was too slow to process the characters received and receive them at the same time. With the IO server and irq update, the issue should be fixed.