Add documentation for the hostName argument

python/core/auth/qgsauthcertutils.sip

@@ -279,6 +279,7 @@ Get short strings describing an SSL error
 %Docstring
  validateCertChain validates the given ``certificateChain``
  \param certificateChain list of certificates to be checked, with leaf first and with optional root CA last
+ \param hostName (optional) name of the host to be verified
  \param addRootCa if true the CA will be added to the trusted CAs for this validation check
  :return: list of QSslError, if the list is empty then the cert chain is valid
  :rtype: list of QSslError

src/core/auth/qgsauthcertutils.h

@@ -299,6 +299,7 @@ class CORE_EXPORT QgsAuthCertUtils
     /**
      * \brief validateCertChain validates the given \a certificateChain
      * \param certificateChain list of certificates to be checked, with leaf first and with optional root CA last
+     * \param hostName (optional) name of the host to be verified
      * \param addRootCa if true the CA will be added to the trusted CAs for this validation check
      * \return list of QSslError, if the list is empty then the cert chain is valid
      */