PEL: Save AdditionalData in a UserData section

Save the contents of the AdditionalData OpenBMC event log property as
JSON in a UserData PEL section.

For example, if the AdditionalData property, which is an array of
strings, looks like:
    ["KEY1=VALUE1", "KEY=VALUE2"]

Then the data stored as ASCII text in the UserData section is:
    {"KEY1":"VALUE1","KEY2":"VALUE2"}

If one of the keys is "ESEL", then that entry is removed from the
UserData output as that contains a full raw PEL from the host sent down
as ASCII text.

Signed-off-by: Matt Spinler <spinler@us.ibm.com>
Change-Id: Ia6ffabb39fdb4315ec2152744414e44f7d2ec4aa
diff --git a/extensions/openpower-pels/user_data_formats.hpp b/extensions/openpower-pels/user_data_formats.hpp
new file mode 100644
index 0000000..53cb5ee
--- /dev/null
+++ b/extensions/openpower-pels/user_data_formats.hpp
@@ -0,0 +1,19 @@
+#pragma once
+
+namespace openpower
+{
+namespace pels
+{
+
+enum class UserDataFormat
+{
+    json = 1
+};
+
+enum class UserDataFormatVersion
+{
+    json = 1
+};
+
+} // namespace pels
+} // namespace openpower