sgsn_libgtp.c: Log pointer of deleted context

Change-Id: I8a4627b54090e72f86a9c5a781670be52522062b
diff --git a/src/gprs/sgsn_libgtp.c b/src/gprs/sgsn_libgtp.c
index 4061e7a..70112cb 100644
--- a/src/gprs/sgsn_libgtp.c
+++ b/src/gprs/sgsn_libgtp.c
@@ -635,7 +635,7 @@
 /* Called whenever a PDP context is deleted for any reason */
 static int cb_delete_context(struct pdp_t *pdp)
 {
-	LOGPDPX(DGPRS, LOGL_INFO, pdp, "Context was deleted\n");
+	LOGPDPX(DGPRS, LOGL_INFO, pdp, "Context %p was deleted\n", pdp);
 
 	return 0;
 }