Change p9_mss_freq_system to write attributes, errors for Cronus

  Honor the maximum support frequencies based on rank configs
  Remove the MEMVPD_FREQ attribute
  Fixup VPD tooling and accessors for new freq attrs
  Fix test case handling of master ranks
  Fix handling of empty MCS in Cronus

Change-Id: I9a2b30308654f3dbd0815be88aa06fd6b3c94bcb
Original-Change-Id: I669ad0e81454f12368b484e826461ee76f7b9079
Reviewed-on: http://ralgit01.raleigh.ibm.com/gerrit1/29878
Reviewed-by: Daniel M. Crowell <dcrowell@us.ibm.com>
Tested-by: Jenkins Server <pfd-jenkins+hostboot@us.ibm.com>
Tested-by: PPE CI <ppe-ci+hostboot@us.ibm.com>
Reviewed-by: ANDRE A. MARIN <aamarin@us.ibm.com>
Reviewed-by: Matt K. Light <mklight@us.ibm.com>
Tested-by: Hostboot CI <hostboot-ci+hostboot@us.ibm.com>
Reviewed-by: Jennifer A. Stofer <stofer@us.ibm.com>
Reviewed-on: http://ralgit01.raleigh.ibm.com/gerrit1/42149
Tested-by: Jenkins OP Build CI <op-jenkins+hostboot@us.ibm.com>
Tested-by: FSP CI Jenkins <fsp-CI-jenkins+hostboot@us.ibm.com>

src/import/chips/p9/procedures/xml/attribute_info/freq_attributes.xml

@@ -55,15 +55,22 @@
     <targetType>TARGET_TYPE_SYSTEM</targetType>
     <description>
       Maximum frequency (in MHz) that this system can run the DIMMs at.
-      There are 4 possible values determined by the dimm configuration.
+      There are 5 possible values determined by the dimm configuration.
+      For configurations which have mixed rank configurations, the lowest
+      frequency based on ranks of either DIMM is chosen. For example if
+      there was a 1R and a 2R DIMM installed, and 1R dual drop was a lower
+      max freq than 2R dual drop, then the 1R max freq would be the max allowed.
         [0]=One rank, single drop
         [1]=Two rank, single drop
-        [2]=One rank, dual drop
-        [3]=Two rank, dual drop
-      A value of zero would indicate an unsupported configuration.
+        [2]=Four rank, single drop
+        [3]=One rank, dual drop
+        [4]=Two rank, dual drop
+      A value of zero would indicate an unsupported configuration. Note: Do not
+      use this attribute to limit configurations, it is not checked during plug rules.
+      If you have an unsupported configuration, use the value 0 as the maximum freq.
     </description>
     <valueType>uint32</valueType>
-    <array>4</array>
+    <array>5</array>
     <platInit/>
   </attribute>
   <!-- ********************************************************************* -->