servicemanager: service_manager missing include for string.h

service_manager.c gets string.h inherited from
private/android_filesystem_config.h it should
not rely on this in the future. The intent is
to move fs_config function into libcutils and
thus deprecate any need for string.h in this
include file.

Bug: 19908228
Change-Id: Icc95ee02bf02c596463868b1330d209d1bd5c58a

cmds/servicemanager/service_manager.c

@@ -1,10 +1,11 @@
 /* Copyright 2008 The Android Open Source Project
  */
 
-#include <stdio.h>
-#include <stdlib.h>
 #include <errno.h>
 #include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
 
 #include <private/android_filesystem_config.h>