Input: bfin_rotary - move pin lists into into platform data

Newer Blackfin boards use pinctrl API to manage pins and the legacy
peripherial lists are not useful on them. Let's move pin lists into
platform data so older boards can still use them and newer boards can use
the modern API.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>