Use last l3 cache object for SIMICS trace

The logic used in this script to choose the correct l3_cache_ram
object is complex. Currently in a multi-node SIMICS system,
the first l3_cache_ram object is always used because it always
has an HRMOR that is at 0x8000000 and all l3_cache_ram objects
have the same priority (0). This change just adjusts the logic
to always use the last l3_cache_ram object in the list that
fits the required memory region and has the same or higher
priority.

Change-Id: I960a5b9f04d934a8823f541c0a95133700cc0120
CQ: SW431167
Reviewed-on: http://ralgit01.raleigh.ibm.com/gerrit1/60050
Tested-by: Jenkins Server <pfd-jenkins+hostboot@us.ibm.com>
Reviewed-by: William G. Hoffa <wghoffa@us.ibm.com>
Tested-by: Jenkins OP Build CI <op-jenkins+hostboot@us.ibm.com>
Tested-by: Jenkins OP HW <op-hw-jenkins+hostboot@us.ibm.com>
Tested-by: FSP CI Jenkins <fsp-CI-jenkins+hostboot@us.ibm.com>
Reviewed-by: Prachi Gupta <pragupta@us.ibm.com>
Reviewed-by: Daniel M. Crowell <dcrowell@us.ibm.com>

src/build/debug/simics-debug-framework.py

@@ -615,7 +615,10 @@ def magic_instruction_callback(user_arg, cpu, arg):
                             low_priority = priority
                             #break
                     break
-                elif priority < low_priority:
+                # If we find an object later in the list that covers the
+                # correct area, and has same or higher priority (indicated
+                # by lower number) then use it.
+                elif priority <= low_priority:
                     mem_object = simics.SIM_object_name(entry[1])
                     #print "Found entry %s for hrmor %d" % (mem_object, hb_hrmor)
                     low_priority = priority