Fix a documentation typo
diff --git a/include/mbedtls/ccm.h b/include/mbedtls/ccm.h
index 3f3a25d..21ba098 100644
--- a/include/mbedtls/ccm.h
+++ b/include/mbedtls/ccm.h
@@ -136,7 +136,7 @@
* 15 - \p iv_len.
* \param add The additional data field. If \p add_len is greater than
* zero, \p add must be a readable buffer of at least that
- * length. If `pad_len == 0`, this may be \c NULL.
+ * length. If `add_len == 0`, this may be \c NULL.
* \param add_len The length of additional data in Bytes.
* This must be less than 2^16 - 2^8.
* \param input The buffer holding the input data. If \p length is greater
@@ -182,7 +182,7 @@
* 15 - \p iv_len.
* \param add The additional data field. If \p add_len is greater than
* zero, \p add must be a readable buffer of at least that
- * length. If `pad_len == 0`, this may be \c NULL.
+ * length. If `add_len == 0`, this may be \c NULL.
* \param add_len The length of additional data in Bytes.
* This must be less than 2^16 - 2^8.
* \param input The buffer holding the input data. If \p length is greater
@@ -222,7 +222,7 @@
* 15 - \p iv_len.
* \param add The additional data field. If \p add_len is greater than
* zero, \p add must be a readable buffer of at least that
- * length. If `pad_len == 0`, this may be \c NULL.
+ * length. If `add_len == 0`, this may be \c NULL.
* \param add_len The length of additional data in Bytes.
* This must be less than 2^16 - 2^8.
* \param input The buffer holding the input data. If \p length is greater
@@ -265,7 +265,7 @@
* 15 - \p iv_len.
* \param add The additional data field. If \p add_len is greater than
* zero, \p add must be a readable buffer of at least that
- * length. If `pad_len == 0`, this may be \c NULL.
+ * length. If `add_len == 0`, this may be \c NULL.
* \param add_len The length of additional data in Bytes.
* This must be less than 2^16 - 2^8.
* \param input The buffer holding the input data. If \p length is greater