switch vfs_mkdir() and ->mkdir() to umode_t

vfs_mkdir() gets int, but immediately drops everything that might not
fit into umode_t and that's the only caller of ->mkdir()...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs/xfs/xfs_iops.c

@@ -241,7 +241,7 @@ STATIC int
 xfs_vn_mkdir(
 	struct inode	*dir,
 	struct dentry	*dentry,
-	int		mode)
+	umode_t		mode)
 {
 	return xfs_vn_mknod(dir, dentry, mode|S_IFDIR, 0);
 }