dt-bindings:iio:imu:adi,adis16480: txt to yaml conversion

Alexandru is currently listed as maintainer on basis of last person
to touch the binding.

Whilst the driver only uses one interrupt, the hardware can route events
to one and dataready signal to the other so we should allow for either
1 or 2 interrupts.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Cc: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20201031184854.745828-12-jic23@kernel.org