MXS-2002 Worker::execute() renamed to Worker::call()

In preparation for Worker::post() to be renamed to Worker:execute().
The concept of _posting_ will be reserved to mean the transfer of
something over the message queue to the worker for processing and
nothing else.

include/maxscale/worker.hh

@@ -771,7 +771,7 @@ public:
      *
      * @return True if function was executed on the worker
      */
-    bool execute(GenericFunction func, enum execute_mode_t mode);
+    bool call(GenericFunction func, enum execute_mode_t mode);
 
     /**
      * Post a message to a worker.

server/core/worker.cc

@@ -516,7 +516,7 @@ bool Worker::post(GenericFunction func, Semaphore* pSem, execute_mode_t mode)
     return rval;
 }
 
-bool Worker::execute(GenericFunction func, execute_mode_t mode)
+bool Worker::call(GenericFunction func, execute_mode_t mode)
 {
     Semaphore sem;
     return post(func, &sem, mode) && sem.wait();

server/modules/monitor/mariadbmon/mariadbmon.cc

@@ -263,7 +263,7 @@ void MariaDBMonitor::diagnostics(DCB *dcb) const
         diag_str = diagnostics_to_string();
     };
 
-    if (!mutable_ptr->execute(func, Worker::EXECUTE_AUTO))
+    if (!mutable_ptr->call(func, Worker::EXECUTE_AUTO))
     {
         diag_str = DIAG_ERROR;
     }
@@ -310,7 +310,7 @@ json_t* MariaDBMonitor::diagnostics_json() const
         rval = diagnostics_to_json();
     };
 
-    if (!mutable_ptr->execute(func, Worker::EXECUTE_AUTO))
+    if (!mutable_ptr->call(func, Worker::EXECUTE_AUTO))
     {
         rval = mxs_json_error_append(rval, "%s", DIAG_ERROR);
     }