hid: Add hid_ioctl method to HID interface

hid_ioctl method executes arbitrary transport backend command.
Format of the command is defined by hardware transport driver.

It is intended to assist HID device drivers to execute non-HID commands
on hybrid devices like Elan and Apple touchpads which can be switched
between HID and proprietary modes.

(cherry picked from commit 5f47c5a3a35de67546ce74cb01d45e62d414a179)