iio: adc: ad7091r: Remove unneeded probe parameters

With the grouping of ad7091r initialization data and callbacks into the
init_info struct, there is no more need to pass the device name and
register map through probe function parameters as those will be available
in the init_info object.
Remove probe parameters that are not needed anymore.

Signed-off-by: Marcelo Schmitt <marcelo.schmitt@analog.com>
Link: https://lore.kernel.org/r/090a6b461410a374511a8c73659de28b2665f96b.1703013352.git.marcelo.schmitt1@gmail.com


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