MFC: Remove obsolete isp_dogactive tag.

Add 8 bits of volatile mailbox busy mask- this will be the bitmask
of output mailbox values we want to get back out of the chip once
a mailbox command is done. Add storage for the maximum number of
output mailbox registers to the softc. Set ISP_MAX_LUNS to be off
of new isp_maxluns tag in softc. Change our 'fabdev' tag to
'loggedin'. Increase size (and add defines for) topology storage.

Roll minor version numbers.