iio: hi8435: remote ampersands from hi8435_info definition

C syntax allows apersands when initializing structures fields with
function pointers, but in Linux sources ampersands are normally not used
in thix context.

Signed-off-by: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>