Defining session const  for multi net session mgmt

This session const will be used in multi session management and session
commands  and replace the existing session const used into lowercamel case

Signed-off-by: Suryakanth Sekar <suryakanth.sekar@linux.intel.com>
Change-Id: I76725acdf5d3d002f82a1076509ed37d668d01d3
diff --git a/include/Makefile.am b/include/Makefile.am
index b7c303a..996c41a 100644
--- a/include/Makefile.am
+++ b/include/Makefile.am
@@ -1,6 +1,7 @@
 nobase_include_HEADERS = \
 	ipmid/api.hpp \
 	ipmid/api-types.hpp \
+	ipmid/sessiondef.hpp \
 	ipmid/filter.hpp \
 	ipmid/handler.hpp \
 	ipmid/message.hpp \