PEL: Create FRUIdentity with FRUs/procedures

Add constructors to the FRUIdentity structure in the SRC section to take
either a hardware callout with PN/SN/CCIN, or a maintenance procedure
callout with a maintenance procedure enum.  Both of these also take
callout priority.

These will be used when creating PELs that have callouts.

Signed-off-by: Matt Spinler <spinler@us.ibm.com>
Change-Id: I5071d98df38b63ba53224c3f3b853e57234ed74e
diff --git a/extensions/openpower-pels/pel_types.hpp b/extensions/openpower-pels/pel_types.hpp
index d23ebe8..f6f66a5 100644
--- a/extensions/openpower-pels/pel_types.hpp
+++ b/extensions/openpower-pels/pel_types.hpp
@@ -131,6 +131,19 @@
 };
 
 /**
+ * @brief Callout priority values
+ */
+enum class CalloutPriority
+{
+    high = 'H',
+    medium = 'M',
+    mediumGroupA = 'A',
+    mediumGroupB = 'B',
+    mediumGroupC = 'C',
+    low = 'L'
+};
+
+/**
  * @brief Maintenance procedure enums
  */
 enum class MaintProcedure