nsflsgs: drop missing.h and use missing_sched.h

src/shared/bus-unit-util.c

@@ -18,6 +18,7 @@
 #include "ip-protocol-list.h"
 #include "list.h"
 #include "locale-util.h"
+#include "missing_fs.h"
 #include "mountpoint-util.h"
 #include "nsflags.h"
 #include "parse-util.h"

src/shared/nsflags.h

@@ -1,9 +1,7 @@
 /* SPDX-License-Identifier: LGPL-2.1+ */
 #pragma once
 
-#include <sched.h>
-
-#include "missing.h"
+#include "missing_sched.h"
 
 /* The combination of all namespace flags defined by the kernel. The right type for this isn't clear. setns() and
  * unshare() expect these flags to be passed as (signed) "int", while clone() wants them as "unsigned long". The latter