ide: call ide_proc_register_driver() later

Call ide_proc_register_driver() in ide*_setup() (just before
ide*_add_settings() call) instead of in ->probe method.

Despite being basically a preparation for /proc/ide/hd*/settings
rework this is a nice cleanup in itself.

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>