cifsd: Fix a use after free on error path

The ksmbd_free_work_struct() frees "work" so we need to swap the order
of these two function calls to avoid a use after free.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Steve French <stfrench@microsoft.com>