crypto: amlogic - Remove prepare/unprepare request

The callbacks for prepare and unprepare request in crypto_engine
is superfluous.  They can be done directly from do_one_request.

Move the code into do_one_request and remove the unused callbacks.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/amlogic/amlogic-gxl-cipher.c

@@ -332,8 +332,6 @@ int meson_cipher_init(struct crypto_tfm *tfm)
 			 crypto_skcipher_reqsize(op->fallback_tfm);
 
 	op->enginectx.op.do_one_request = meson_handle_cipher_request;
-	op->enginectx.op.prepare_request = NULL;
-	op->enginectx.op.unprepare_request = NULL;
 
 	return 0;
 }