d_path: Make seq_path() use a struct path argument
seq_path() is always called with a dentry and a vfsmount from a struct path.
Make seq_path() take it directly as an argument.
Signed-off-by: Jan Blunck <jblunck@suse.de> Cc: Christoph Hellwig <hch@lst.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: "J. Bruce Fields" <bfields@fieldses.org> Cc: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>