projects/mfi_head to -current next week

Hi folks,

I'd like to start merging mfi(4) from projects/head_mfi into -current
next week.  The mfi(4) driver is stable and I don't know of any issues
with it now.  I fixed a few issues that I knew of this past week.  Several
people have contributed to this.  LSI did the base HW support.  This
update supports all current mfi based cards.  It supports JBOD via creating
/sys/mfisyspd* entries for each disk.  When a disk is pulled from the
controller the node goes away and when a disk is inserted it creates an
entry.  Using a fairly new MegaCli, it can also control how JBOD support
works.  We may need to update our port.  This JBOD support is not the same
as CAM pass through that some have hacked to make disks appear as da*.

Several people are using this driver now so I feel it is stable enough
to hit the tree.  More eyes and people using this will make it better.
This new HW is showing up more and more in new systems so it will make
it easier for people to use FreeBSD on these machines and have it just
work.

Thanks to LSI for the initial HW support and all of the people that have
been testing and getting it in shape to commit.

Doug A.