xfs: don't call xfs_file_open from xfs_dir_open

Directories do not support direct I/O and thus no non-blocking direct
I/O either.  Open code the shutdown check and call to generic_file_open
instead.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240423124608.537794-4-hch@lst.de
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

fs/xfs/xfs_file.c

@@ -1243,7 +1243,9 @@ xfs_dir_open(
 	unsigned int	mode;
 	int		error;
 
-	error = xfs_file_open(inode, file);
+	if (xfs_is_shutdown(ip->i_mount))
+		return -EIO;
+	error = generic_file_open(inode, file);
 	if (error)
 		return error;