ANDROID: mnt: Add filesystem private data to mount points

This starts to add private data associated directly
to mount points. The intent is to give filesystems
a sense of where they have come from, as a means of
letting a filesystem take different actions based on
this information.

Change-Id: Ie769d7b3bb2f5972afe05c1bf16cf88c91647ab2
Signed-off-by: Daniel Rosenberg <drosen@google.com>
diff --git a/include/linux/mount.h b/include/linux/mount.h
index 45b1f56..1ff21c1 100644
--- a/include/linux/mount.h
+++ b/include/linux/mount.h
@@ -68,6 +68,7 @@ struct vfsmount {
 	struct dentry *mnt_root;	/* root of the mounted tree */
 	struct super_block *mnt_sb;	/* pointer to superblock */
 	int mnt_flags;
+	void *data;
 } __randomize_layout;
 
 struct file; /* forward dec */