callouts: implement metadata handler

Implement handler of the metadata CALLOUT_DEVICE_PATH. This handler will
convert a device path to an inventory path and call out the latter.

Change-Id: Icbf9c841884ec139f35ea2ac94648e355b421bb2
Signed-off-by: Deepak Kodihalli <dkodihal@in.ibm.com>
diff --git a/Makefile.am b/Makefile.am
index c9aa9f8..6ca02d3 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -9,7 +9,7 @@
 	xyz/openbmc_project/Logging/Internal/Manager/server.hpp
 
 libphosphor_logging_FILES = \
-	elog.cpp
+	elog.cpp elog_meta.cpp
 libphosphor_loggingdir = ${libdir}
 libphosphor_logging_LTLIBRARIES = libphosphor_logging.la
 libphosphor_logging_la_SOURCES = $(libphosphor_logging_FILES)
@@ -35,7 +35,8 @@
 	elog-lookup.cpp \
 	elog_entry.cpp \
 	org.openbmc.Associations.cpp \
-	elog-process-metadata.cpp
+	elog-process-metadata.cpp \
+	elog_meta.cpp
 
 # Be sure to build needed files before compiling
 BUILT_SOURCES = \