crypto: aes - Move key_length in struct crypto_aes_ctx to be the last field

The Intel AES-NI AES acceleration instructions need key_enc, key_dec
in struct crypto_aes_ctx to be 16 byte aligned, it make this easier to
move key_length to be the last one.

Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
diff --git a/include/crypto/aes.h b/include/crypto/aes.h
index 656a4c6..7524ba3 100644
--- a/include/crypto/aes.h
+++ b/include/crypto/aes.h
@@ -17,10 +17,14 @@
 #define AES_MAX_KEYLENGTH	(15 * 16)
 #define AES_MAX_KEYLENGTH_U32	(AES_MAX_KEYLENGTH / sizeof(u32))
 
+/*
+ * Please ensure that the first two fields are 16-byte aligned
+ * relative to the start of the structure, i.e., don't move them!
+ */
 struct crypto_aes_ctx {
-	u32 key_length;
 	u32 key_enc[AES_MAX_KEYLENGTH_U32];
 	u32 key_dec[AES_MAX_KEYLENGTH_U32];
+	u32 key_length;
 };
 
 extern const u32 crypto_ft_tab[4][256];