linuxkpi: Add kthread_run_worker()

On Linux, kthread_run_worker() differs from kthread_create_worker()
by waking up the task after creating it with kthread_create_worker().

On FreeBSD, we already execute it and wait for it, so probably no need
to do anything further. Therefore, kthread_run_worker() is an alias to
kthread_create_worker().

The DRM drivers generic code started to replace
kthread_create_worker() by kthread_run_worker() as is in Linux 6.14.

Reviewed by: bz
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D57701