PEL: Add ExtendedUserHeader section class

This is a required PEL section.

The section contains:
* The machine type/model/SN
* The server firmware version
* The BMC firmware version
* The 'Event Common Reference Time' (not used yet)
* The symptom ID (a unique event signature)

Signed-off-by: Matt Spinler <spinler@us.ibm.com>
Change-Id: I223041f85965195fccf69542dbe86ce856073b36
diff --git a/extensions/openpower-pels/openpower-pels.mk b/extensions/openpower-pels/openpower-pels.mk
index 35b1b29..5bce70d 100644
--- a/extensions/openpower-pels/openpower-pels.mk
+++ b/extensions/openpower-pels/openpower-pels.mk
@@ -14,6 +14,7 @@
 	extensions/openpower-pels/callout.cpp \
 	extensions/openpower-pels/callouts.cpp \
 	extensions/openpower-pels/data_interface.cpp \
+	extensions/openpower-pels/extended_user_header.cpp \
 	extensions/openpower-pels/failing_mtms.cpp \
 	extensions/openpower-pels/fru_identity.cpp \
 	extensions/openpower-pels/generic.cpp \