proc: Split the namespace stuff out into linux/proc_ns.h

Split the proc namespace stuff out into linux/proc_ns.h.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: netdev@vger.kernel.org
cc: Serge E. Hallyn <serge.hallyn@ubuntu.com>
cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/kernel/user.c b/kernel/user.c
index e81978e..5bbb919 100644
--- a/kernel/user.c
+++ b/kernel/user.c
@@ -16,7 +16,7 @@
 #include <linux/interrupt.h>
 #include <linux/export.h>
 #include <linux/user_namespace.h>
-#include <linux/proc_fs.h>
+#include <linux/proc_ns.h>
 
 /*
  * userns count is 1 for root user, 1 for init_uts_ns,