ksmbd: fix uninitialized pointer read in ksmbd_vfs_rename()

Uninitialized rd.delegated_inode can be used in vfs_rename().
Fix this by setting rd.delegated_inode to NULL to avoid the uninitialized
read.

Fixes: 74d7970feb ("ksmbd: fix racy issue from using ->d_parent and ->d_name")
Reported-by: Coverity Scan <scan-admin@coverity.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>

fs/smb/server/vfs.c

@@ -743,6 +743,7 @@ retry:
 	rd.new_dir		= new_path.dentry->d_inode,
 	rd.new_dentry		= new_dentry,
 	rd.flags		= flags,
+	rd.delegated_inode	= NULL,
 	err = vfs_rename(&rd);
 	if (err)
 		ksmbd_debug(VFS, "vfs_rename failed err %d\n", err);