[VOL-4676]:
Initial Framework for reading SFP capabilities by reading the EEPROM data.
Use the detected SFP data to derive the MAC and PON system mode.
Make the SFP EEPROM read mode configurable per platform through the
DYNAMIC_PON_TRX_SUPPORT '#define' defined in the platform vendor.h file.

Change-Id: I07d7763371d2f804a1e93ca38646b1a30198f8ee
diff --git a/agent/common/core.h b/agent/common/core.h
index 2159716..4279f35 100644
--- a/agent/common/core.h
+++ b/agent/common/core.h
@@ -23,6 +23,7 @@
 #include <voltha_protos/ext_config.grpc.pb.h>
 
 #include "state.h"
+#include "vendor.h"
 
 extern "C"
 {
@@ -199,6 +200,7 @@
 
 #define LOGICAL_DISTANCE(MLD,EQD,TD) (MLD-(EQD*TD)*102) /* Round-trip time of 102 meters is 1us */
 extern State state;
+extern PonTrx ponTrx;
 
 //***************************************//
 // Function declations used by the core. //