ksmbd: fix an oops in error handling in smb2_open()

If smb2_get_name() then name is an error pointer.  In the clean up
code, we try to kfree() it and that will lead to an Oops.  Set it to
NULL instead.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

fs/ksmbd/smb2pdu.c

@@ -2462,6 +2462,7 @@ int smb2_open(struct ksmbd_work *work)
 			rc = PTR_ERR(name);
 			if (rc != -ENOMEM)
 				rc = -ENOENT;
+			name = NULL;
 			goto err_out1;
 		}