Send the OK outside the KILL functions

By sending the OK for the KILL commands outside the function, they can be
used to kill connections that do not expect responses.

server/modules/protocol/MySQL/mariadbclient/mysql_client.cc

@@ -2030,6 +2030,7 @@ static spec_com_res_t process_special_commands(DCB* dcb, GWBUF* read_buffer, int
             {
                 uint64_t process_id = gw_mysql_get_byte4(bytes);
                 mxs_mysql_execute_kill(dcb->session, process_id, KT_CONNECTION);
+                mxs_mysql_send_ok(dcb, 1, 0, NULL);
                 rval = RES_END;
             }
         }
@@ -2106,6 +2107,8 @@ spec_com_res_t handle_query_kill(DCB* dcb,
                 {
                     mxs_mysql_execute_kill_user(dcb->session, user.c_str(), kt);
                 }
+
+                mxs_mysql_send_ok(dcb, 1, 0, NULL);
             }
         }
     }