cgroup.c: fix some compilation warnings

Fix the following warnings:
| cgroup.c:296:13: warning: implicit declaration of function 'conf_any_change' [-Wimplicit-function-declaration]
| cgroup.c:297:17: warning: implicit declaration of function 'service_reload_dynamic' [-Wimplicit-function-declaration]

Signed-off-by: Ming Liu <liu.ming50@gmail.com>

src/cgroup.c

@@ -37,6 +37,8 @@
 #include "cgroup.h"
 #include "finit.h"
 #include "iwatch.h"
+#include "conf.h"
+#include "service.h"
 #include "log.h"
 #include "util.h"