PM: Added hcode image build support for SGPE and CME.

In this commit, nested xip structure of hardware image is traversed and hcode
for following platform is copied to to relevant area in HOMER:
    - SGPE
    - CME
    - P9 Self Restore code

RTC: 145583
Change-Id: I8f91e34aff81b4c9218be5a380e3336913cbd7c9
Reviewed-on: http://ralgit01.raleigh.ibm.com/gerrit1/10675
Tested-by: Jenkins Server
Tested-by: Auto Mirror
Reviewed-by: AMIT KUMAR <akumar3@us.ibm.com>
Tested-by: Hostboot CI
Reviewed-by: Daniel M. Crowell <dcrowell@us.ibm.com>
Reviewed-by: Gregory S. Still <stillgs@us.ibm.com>
Reviewed-on: http://ralgit01.raleigh.ibm.com/gerrit1/41214
Tested-by: Jenkins Server <pfd-jenkins+hostboot@us.ibm.com>
Reviewed-by: Sachin Gupta <sgupta2m@in.ibm.com>

src/import/chips/p9/procedures/xml/attribute_info/p9_hcode_image_build_attributes.xml

@@ -0,0 +1,39 @@
+<!-- IBM_PROLOG_BEGIN_TAG                                                   -->
+<!-- This is an automatically generated prolog.                             -->
+<!--                                                                        -->
+<!-- $Source: src/import/chips/p9/procedures/xml/attribute_info/p9_hcode_image_build_attributes.xml $ -->
+<!--                                                                        -->
+<!-- OpenPOWER sbe Project                                                  -->
+<!--                                                                        -->
+<!-- Contributors Listed Below - COPYRIGHT 2016,2017                        -->
+<!-- [+] International Business Machines Corp.                              -->
+<!--                                                                        -->
+<!--                                                                        -->
+<!-- Licensed under the Apache License, Version 2.0 (the "License");        -->
+<!-- you may not use this file except in compliance with the License.       -->
+<!-- You may obtain a copy of the License at                                -->
+<!--                                                                        -->
+<!--     http://www.apache.org/licenses/LICENSE-2.0                         -->
+<!--                                                                        -->
+<!-- Unless required by applicable law or agreed to in writing, software    -->
+<!-- distributed under the License is distributed on an "AS IS" BASIS,      -->
+<!-- WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or        -->
+<!-- implied. See the License for the specific language governing           -->
+<!-- permissions and limitations under the License.                         -->
+<!--                                                                        -->
+<!-- IBM_PROLOG_END_TAG                                                     -->
+<!--nest_attributes.xml-->
+<attributes>
+<!-- ********************************************************************** -->
+<attribute>
+  <id>ATTR_FUSED_CORE_MODE</id>
+  <targetType>TARGET_TYPE_SYSTEM</targetType>
+  <description>
+    Summarizes the fused status of cores. This is same for all P9 chips
+    in the system. If a core is in a fused state, attribute should read 1 
+    else zero. It needs to be populated during ipl but before istep 15.
+  </description>
+  <valueType>uint8</valueType>
+  <platInit/>
+</attribute>
+</attributes>