Update for MCBIST region
Update for MCBIST region

The MCBIST scom satellite only uses
2 bits for its satellite id.

Change-Id: Iedf7e80b821d80e1bdd476afa87dcdbcf2236189
Reviewed-on: http://gfw160.aus.stglabs.ibm.com:8080/gerrit/23250
Tested-by: Jenkins Server
Reviewed-by: Brent Wieman <cab499b31cd4c652b90b4682871101e72d52e19a@us.ibm.com>
Reviewed-by: Thi N. Tran <25a2bca7ae5a8ea03be09ca8d282480c08c13052@us.ibm.com>
Reviewed-by: Jennifer A. Stofer <ab93eca12e43608f33daa16a67357cd7b7e867ab@us.ibm.com>

open-power/hostboot,open-power/hostboot,open-power/hostboot,open-power/hostboot,open-power/hostboot