If the mps/mpr(4) device has corrupted or missing firmware then
it will fail to attach at boot.
Add a new mpsutil hostboot command, to reset the device and boot
from firmware loaded from host memory.
Also add an interface to use firmware(9) to load the firmware at boot.
Loosely based on https://github.com/marcan/lsirec/
Assisted by: Claude Code (Sonnet 5)
Sponsored by: Klara, Inc.