crypto: fix build without scrypt

* add missing semicolon to fix:
  In file included from ../src/node_crypto.h:47,
                   from ../src/node.cc:46:
  ../src/crypto/crypto_scrypt.h:80:2:
  error: expected ';' after struct definition
     80 | }
        |  ^
        |  ;

  and fix typo in the comment

Signed-off-by: Martin Jansa <martin.jansa@lge.com>

PR-URL: https://github.com/nodejs/node/pull/40613


Reviewed-By: Tobias Nießen <tniessen@tnie.de>
Reviewed-By: Voltrex <mohammadkeyvanzade94@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>