PEL: Validate the Action Flags field

According to the PEL spec, the Action Flags and Event Type fields in the
User Header section must be in agreement with the Severity field. So,
when a PEL is being created from an OpenBMC event log, check those
values for correctness and fix them up if required.

In addition, as those fields are optional in the message registry, this
code will also just set these two fields to valid values if they were
left out.

The rules being followed are documented in the PEL readme.

Signed-off-by: Matt Spinler <spinler@us.ibm.com>
Change-Id: Iad88de5080ba79a9ff31f962ef99bfc11994b9ed
diff --git a/extensions/openpower-pels/user_header.hpp b/extensions/openpower-pels/user_header.hpp
index 459952b..b382a84 100644
--- a/extensions/openpower-pels/user_header.hpp
+++ b/extensions/openpower-pels/user_header.hpp
@@ -102,6 +102,16 @@
     }
 
     /**
+     * @brief Set the event type field
+     *
+     * @param[in] type - the new event type
+     */
+    void setEventType(uint8_t type)
+    {
+        _eventType = type;
+    }
+
+    /**
      * @brief Returns the problem domain field.
      *
      * @return uint8_t - the problem domain
@@ -132,6 +142,16 @@
     }
 
     /**
+     * @brief Sets the action flags field
+     *
+     * @param[in] flags - the new action flags
+     */
+    void setActionFlags(uint16_t flags)
+    {
+        _actionFlags = flags;
+    }
+
+    /**
      * @brief Returns the size of this section when flattened into a PEL
      *
      * @return size_t - the size of the section