Increase size allocated for HBRT section in Pnor from 4.5 -> 6.0 MB
Increase size allocated for HBRT section in Pnor from 4.5 -> 6.0 MB

Due to recent commits we were going over the limit of the HBRT section
in pnor when running hb prime --test. This commit increments the size
of the HBRT section for the default pnor layout

Change-Id: I19064da16535e68ca649a675dfae166d64d9f4bd
Reviewed-on: http://ralgit01.raleigh.ibm.com/gerrit1/51255
Reviewed-by: Prachi Gupta <25a72946fc4ec2539bba3cff1fbb2916af6a7649@us.ibm.com>
Reviewed-by: William G. Hoffa <7dd6aa5e78423995d9d7c7ecada5b77ee07f88cc@us.ibm.com>
Tested-by: Jenkins Server <8e3f934e4c44875bc48d33da3ea13d93ba9a233f@us.ibm.com>
Reviewed-by: Christian R. Geddes <f397583a9caa8163a06ad1128784fb67413f2fe6@us.ibm.com>

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