Improve some documentation and ChangeLog entry
diff --git a/ChangeLog b/ChangeLog
index a4f3ae5..d4e754b 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -23,10 +23,14 @@
modules.
Features
- * Add new config.h flag MBEDTLS_CHECK_PARAMS that enables validation of
- more of the parameters by public API functions (see its documentation in
- config.h for details). Disabled by default - requires users to provide an
- implementation of the callback function or macro.
+ * Add a new config.h option of MBEDTLS_CHECK_PARAMS that enables additional
+ validation of parameters in the library's public interface. This does not
+ change the API of existing functions, but additional clarity has been
+ added to the defined documentation interface to make clearer what the
+ interface is designed to accept. See the corresponding API documentation
+ for each function to see what parameter values are defined as invalid.
+ This feature is disabled by default. See its API documentation in
+ config.h for additional steps you have to take when enabling it.
New deprecations
* Deprecate mbedtls_ctr_drbg_update and mbedtls_hmac_drbg_update