mgmt: ignore ksk when dsk is specified in ManagementTool::createZone

Change-Id: I41f530753ded411a0a5c3611fce6c9c8731cde94
Refs: #2249
diff --git a/src/mgmt/management-tool.hpp b/src/mgmt/management-tool.hpp
index 5eabffe..bb13c1e 100644
--- a/src/mgmt/management-tool.hpp
+++ b/src/mgmt/management-tool.hpp
@@ -91,8 +91,9 @@
    *  @param cacheTtl default TTL for RR sets in the zone
    *  @param certValidity validity for automatically created DSK certificate (@p dskCertName
    *                      should not be empty)
-   *  @param kskCertName if given, a zone will be created with this ksk certificate and its key
-   *  @param dskCertName if given, a zone will be created with this dsk certificate and its key
+   *  @param kskCertName if given, a zone will be created with this ksk certificate
+   *  @param dskCertName if given, a zone will be created with this dsk certificate and provided
+   *  ksk certificate will be ignored
    */
   void
   createZone(const Name& zoneName,