Input: opencores-kbd - switch to using managed resources

This change switch to managed resources to simplifies error handling
and module unloading and does away with platform_driver remove function.

Signed-off-by: Pramod Gurav <pramod.gurav@smartplayin.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

diff --cc drivers/input/keyboard/opencores-kbd.c
Simple merge