tree-wide: Sort includes

This was done by running a locally built clang-format with
https://github.com/llvm/llvm-project/pull/137617 and
https://github.com/llvm/llvm-project/pull/137840 applied on all .c
and .h files.

src/shared/socket-netlink.c

@@ -1,10 +1,9 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 
-/* Make sure the net/if.h header is included before any linux/ one */
-#include <net/if.h>
 #include <arpa/inet.h>
 #include <errno.h>
 #include <linux/net_namespace.h>
+#include <net/if.h>
 #include <string.h>
 
 #include "alloc-util.h"