MFC r302031

• No log bit in IOCStatus and endian-safe changes.

Use MPI2_IOCSTATUS_MASK when checking IOCStatus to mask off the log bit, and
make a few more things endian-safe.

• Fix possible use of invalid pointer.

It was possible to use an invalid pointer to get the target ID value. To fix
this, initialize a local Target ID variable to an invalid value and change that
variable to a valid value only if the pointer to the Target ID is not NULL.

• No need to set the MPSSAS_SHUTDOWN flag because it's never used.

• done_ccb pointer can be used if it is NULL.

To prevent this, move check for done_ccb == NULL to before done_ccb is used in
mpssas_stop_unit_done().

• Disks can go missing until a reboot is done in some cases.

This is due to the DevHandle not being released, which causes the Firmware to
not allow that disk to be re-added.

Approved by: ken, scottl, ambrisko (mentors)