ide-disk: use to_ide_drv() and ide_drv_g()

There should be no functional changes caused by this patch.

Cc: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

diff --cc drivers/ide/ide-disk.c
Simple merge

diff --cc drivers/ide/ide-disk.h
Simple merge

diff --cc drivers/ide/ide-disk_ioctl.c
Simple merge