IPL_BIO -> IPL_VM

No functional change. No code change... It's the same thing!
Don't call ifmedia_ioctl with holding locks
Mailbox improvements from mlelstv@

Serialise access to the mailbox and use interrupts.

XXX if (cold) should go
fwrev is a timestamp, print in decimal.
Tidy up locking in wm_ioctl