Fix style issues and a typo
diff --git a/include/mbedtls/ssl.h b/include/mbedtls/ssl.h
index aabbb83..35e5764 100644
--- a/include/mbedtls/ssl.h
+++ b/include/mbedtls/ssl.h
@@ -2124,7 +2124,7 @@
*
* \warning In multi-threaded environments, the callback \p f_ca_cb
* must be thread-safe, and it is the user's responsibility
- * to guaranteee this (for example through a mutex
+ * to guarantee this (for example through a mutex
* contained in the callback context pointed to by \p p_ca_cb).
*/
void mbedtls_ssl_conf_ca_cb( mbedtls_ssl_config *conf,