parisc: use the new LED disk activity trigger

- platform: rename 'ide-disk' to 'disk-activity'

Signed-off-by: Stephan Linz <linz@li-pro.net>
Acked-by: Helge Deller <deller@gmx.de>
Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
2 files changed