Fix typos and pointer math.

Change-Id: I07f33a57454d013844b56bc3e57fe0a271e8b38c
diff --git a/include/ndk/NdkMediaCodec.h b/include/ndk/NdkMediaCodec.h
index 5233fe3..28d121c 100644
--- a/include/ndk/NdkMediaCodec.h
+++ b/include/ndk/NdkMediaCodec.h
@@ -179,7 +179,7 @@
         size_t *encryptedbytes);
 
 /**
- * delete an AMediaCodecCryptoInfo create previously with AMediaCodecCryptoInfo_new, or
+ * delete an AMediaCodecCryptoInfo created previously with AMediaCodecCryptoInfo_new, or
  * obtained from AMediaExtractor
  */
 int AMediaCodecCryptoInfo_delete(AMediaCodecCryptoInfo*);