crypto: n2 - Remove unused struct 'n2_skcipher_request_context'

'n2_skcipher_request_context' was added in
commit 23a6564a ("crypto: niagara2 - switch to skcipher API")
but never used.
Remove it.
Signed-off-by: Dr. David Alan Gilbert <linux@treblig.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/n2_core.c

@@ -720,10 +720,6 @@ static inline struct n2_skcipher_alg *n2_skcipher_alg(struct crypto_skcipher *tf
 	return container_of(alg, struct n2_skcipher_alg, skcipher);
 }
 
-struct n2_skcipher_request_context {
-	struct skcipher_walk	walk;
-};
-
 static int n2_aes_setkey(struct crypto_skcipher *skcipher, const u8 *key,
 			 unsigned int keylen)
 {