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>
diff --git a/fs/gfs2/inode.c b/fs/gfs2/inode.c
index cfd4959..eecfc39c0 100644
--- a/fs/gfs2/inode.c
+++ b/fs/gfs2/inode.c
@@ -1129,7 +1129,7 @@
  * Returns: errno
  */
 
-static int gfs2_mkdir(struct inode *dir, struct dentry *dentry, int mode)
+static int gfs2_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
 {
 	return gfs2_create_inode(dir, dentry, S_IFDIR | mode, 0, NULL, 0, 0);
 }