Fix default on ATTR_MSS_MRW_SUPPORTED_FREQ to be 4 entries

  Fixes errors caused by having array size 4, but 6 entries in the default

Change-Id: Ie9d17ae1ba3050feaa19acc4ef1d34b20038289b
Reviewed-on: http://rchgit01.rchland.ibm.com/gerrit1/75788
Reviewed-by: Mark Pizzutillo <mark.pizzutillo@ibm.com>
Tested-by: FSP CI Jenkins <fsp-CI-jenkins+hostboot@us.ibm.com>
Tested-by: Jenkins Server <pfd-jenkins+hostboot@us.ibm.com>
Tested-by: HWSV CI <hwsv-ci+hostboot@us.ibm.com>
Tested-by: Hostboot CI <hostboot-ci+hostboot@us.ibm.com>
Dev-Ready: Steven B. Janssen <janssens@us.ibm.com>
Reviewed-by: STEPHEN GLANCY <sglancy@us.ibm.com>
Reviewed-by: Jennifer A. Stofer <stofer@us.ibm.com>
Reviewed-on: http://rchgit01.rchland.ibm.com/gerrit1/75804
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Tested-by: Jenkins OP HW <op-hw-jenkins+hostboot@us.ibm.com>
Reviewed-by: Christian R. Geddes <crgeddes@us.ibm.com>

src/import/generic/procedures/xml/attribute_info/generic_memory_mrw_attributes.xml

@@ -41,7 +41,7 @@
       MT2933 = 2933,
       MT3200 = 3200
     </enum>
-    <default> 1866, 2133, 2400, 2666, 2933, 3200 </default>
+    <default> 1866, 2133, 2400, 2666 </default>
     <mssUnit>MT/s</mssUnit>
   </attribute>