tree-wide: code improvements suggested by Coccinelle
diff --git a/man/vtable-example.c b/man/vtable-example.c
index a2a6cd1..98c20ee 100644
--- a/man/vtable-example.c
+++ b/man/vtable-example.c
@@ -59,7 +59,7 @@
                                  vtable,
                                  &object));
 
-  while (true) {
+  for (;;) {
     check(sd_bus_wait(bus, UINT64_MAX));
     check(sd_bus_process(bus, NULL));
   }