Explicitly set pgid and sid of init process

Explicitly set pgid and sid of init process to 1.
Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Serge Hallyn <serue@us.ibm.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: <containers@lists.osdl.org>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

init/main.c

@@ -801,6 +801,7 @@ static int __init kernel_init(void * unused)
 	 */
 	init_pid_ns.child_reaper = current;
 
+	__set_special_pids(1, 1);
 	cad_pid = task_pid(current);
 
 	smp_prepare_cpus(max_cpus);