PEL: Store transmission states in UserHeader

Use a reserved word in the UserHeader section to store some
PEL states:

* Host Transmission State:
  - States involving the progression of a PEL being sent to the
    operating system.

* HMC Transmission State:
  - States involving the progression of a PEL being sent to the
    hardware management console, if there is one attached.

  - Usually, an HMC refers to a specific set of hardware and software
    sold by IBM that connects to OpenPower systems which has specific
    software to deal with receiving PELs.

It is possible that there is an implementation that won't need to send
PELs to either of these entities, in which case these states will
just be unused and left at zero.

This is the same location that other service processor implementations
have stored transmission states.

Signed-off-by: Matt Spinler <spinler@us.ibm.com>
Change-Id: I6a2bfee15336dbd564aeaded88effa55ede0d6c4
diff --git a/extensions/openpower-pels/user_header.cpp b/extensions/openpower-pels/user_header.cpp
index 9258e78..5aef28d 100644
--- a/extensions/openpower-pels/user_header.cpp
+++ b/extensions/openpower-pels/user_header.cpp
@@ -34,14 +34,14 @@
 {
     stream >> _header >> _eventSubsystem >> _eventScope >> _eventSeverity >>
         _eventType >> _reserved4Byte1 >> _problemDomain >> _problemVector >>
-        _actionFlags >> _reserved4Byte2;
+        _actionFlags >> _states;
 }
 
 void UserHeader::flatten(Stream& stream) const
 {
     stream << _header << _eventSubsystem << _eventScope << _eventSeverity
            << _eventType << _reserved4Byte1 << _problemDomain << _problemVector
-           << _actionFlags << _reserved4Byte2;
+           << _actionFlags << _states;
 }
 
 UserHeader::UserHeader(const message::Entry& entry,
@@ -89,7 +89,7 @@
     // These will be cleaned up later in pel_rules::check()
     _actionFlags = entry.actionFlags.value_or(0);
 
-    _reserved4Byte2 = 0;
+    _states = 0;
 
     _valid = true;
 }