crypto: doc - Fix typo in crypto-API.xml

This patch fix some typos found in crypto-API.xml.
It is because the file is generated from comments in sources,
so I had to fix typo in sources.

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Acked-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
diff --git a/include/crypto/aead.h b/include/crypto/aead.h
index 5cb0066..7169ad0 100644
--- a/include/crypto/aead.h
+++ b/include/crypto/aead.h
@@ -33,7 +33,7 @@
  *
  * The example code provided for the asynchronous block cipher operation
  * applies here as well. Naturally all *ablkcipher* symbols must be exchanged
- * the *aead* pendants discussed in the following. In addtion, for the AEAD
+ * the *aead* pendants discussed in the following. In addition, for the AEAD
  * operation, the aead_request_set_assoc function must be used to set the
  * pointer to the associated data memory location before performing the
  * encryption or decryption operation. In case of an encryption, the associated