mps(4): Remove unnecessary assignment (cam_calc_geometry() sets it).
ciss(4): Add forgotten D_MPSAFE to dev_ops and use callout_init_mp().
mps(4): Add forgotten D_MPSAFE to dev_ops and use callout_init_mp().
kernel: Add D_MPSAFE to the ops of mfi(4), mrsas(4) and twa(4).

I overlooked it when I ported them.
kernel/usched: Make the bootverbose messages a bit more informative.

Talk about which scheduler this is about.

While here, change Sibs -> siblings.
mpt(4): Add D_MPSAFE to ops.
isp(4): Remove wrong D_DISK and add D_MPSAFE to ops.