PEL: OpenBMC event log sev to PEL sev helper

Add a function to map the OpenBMC event log severity values to PEL
severity values.

When creating a PEL from an OpenBMC event log, the event log will have
its own severity property, and if the PEL message registry entry for
that error doesn't supply its own severity (it's optional), use this
function to come up with the PEL severity value to use.

Signed-off-by: Matt Spinler <spinler@us.ibm.com>
Change-Id: I66aa001265d8acadb165de874e4ade03a8e28007
diff --git a/extensions/openpower-pels/severity.hpp b/extensions/openpower-pels/severity.hpp
new file mode 100644
index 0000000..f2b9921
--- /dev/null
+++ b/extensions/openpower-pels/severity.hpp
@@ -0,0 +1,20 @@
+#pragma once
+
+#include "elog_entry.hpp"
+
+namespace openpower
+{
+namespace pels
+{
+
+/**
+ * @brief Convert an OpenBMC event log severity to a PEL severity
+ *
+ * @param[in] severity - The OpenBMC event log severity
+ *
+ * @return uint8_t - The PEL severity value
+ */
+uint8_t convertOBMCSeverityToPEL(phosphor::logging::Entry::Level severity);
+
+} // namespace pels
+} // namespace openpower