firewire: ohci: use from_work() macro to expand parent structure of work_struct

firewire: ohci: use from_work() macro to expand parent structure of work_struct

A commit 60b2ebf48526 ("workqueue: Introduce from_work() helper for cleaner
callback declarations") introduces a new macro to retrieve a poiner for the
parent structure of the work item. It is convenient to reduce input text.

This commit uses the macro in PCI driver for 1394 OHCI.

Link: https://lore.kernel.org/r/20250608233808.202355-2-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>