hlr: Export + Declare global g_hlr symbol

Change-Id: I6f3e50f071fb2fbbe58413b4760dc2215055a444
diff --git a/src/hlr.c b/src/hlr.c
index 8732587..0b1ff4f 100644
--- a/src/hlr.c
+++ b/src/hlr.c
@@ -43,7 +43,7 @@
 #include "luop.h"
 #include "hlr_vty.h"
 
-static struct hlr *g_hlr;
+struct hlr *g_hlr;
 static int quit = 0;
 
 /* Trigger 'Insert Subscriber Data' messages to all connected GSUP clients.