PEL: Support user supplied flag to indicate a fatal/terminating

User can supply SEVERITY_DETAIL=SYSTEM_TERM as part
of AdditionalData entry in the event log to set the
severity level in User Header of PEL

Tested: I ran unit test using docker. Also tested manually
by setting D-bus event log

Change-Id: I9205c084c32576734c2b5b4c79c273f8defde9d4
Signed-off-by: Vijay Lobo <vijaylobo@gmail.com>
diff --git a/extensions/openpower-pels/pel.cpp b/extensions/openpower-pels/pel.cpp
index f66d985..48dff51 100644
--- a/extensions/openpower-pels/pel.cpp
+++ b/extensions/openpower-pels/pel.cpp
@@ -55,7 +55,8 @@
 
     _ph = std::make_unique<PrivateHeader>(regEntry.componentID, obmcLogID,
                                           timestamp);
-    _uh = std::make_unique<UserHeader>(regEntry, severity, dataIface);
+    _uh = std::make_unique<UserHeader>(regEntry, severity, additionalData,
+                                       dataIface);
 
     // Extract any callouts embedded in an FFDC file.
     if (!ffdcFiles.empty())