vfs: Suppress MS_* flag defs within the kernel unless explicitly enabled

Only the mount namespace code that implements mount(2) should be using the
MS_* flags.  Suppress them inside the kernel unless uapi/linux/mount.h is
included.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Reviewed-by: David Howells <dhowells@redhat.com>

init/do_mounts.c

@@ -22,6 +22,7 @@
 #include <linux/nfs_fs.h>
 #include <linux/nfs_fs_sb.h>
 #include <linux/nfs_mount.h>
+#include <uapi/linux/mount.h>
 
 #include "do_mounts.h"
 

init/do_mounts_initrd.c

@@ -8,6 +8,7 @@
 #include <linux/sched.h>
 #include <linux/freezer.h>
 #include <linux/kmod.h>
+#include <uapi/linux/mount.h>
 
 #include "do_mounts.h"