Fix no-return-in-nonvoid-functions in osmo-qcdiag-log.c

[    4s] E: osmo-qcdiag no-return-in-nonvoid-function osmo-qcdiag-log.c:170

[hfreyther: Changed exit to return EXIT_SUCCESS]
diff --git a/src/osmo-qcdiag-log.c b/src/osmo-qcdiag-log.c
index 07101b0..c16fe06 100644
--- a/src/osmo-qcdiag-log.c
+++ b/src/osmo-qcdiag-log.c
@@ -167,4 +167,6 @@
 #endif
 
 	}
+
+	return EXIT_SUCCESS;
 }