Use wxDELETE() and wxDELETEA() when possible.

Use wxDELETE[A]() functions which automatically NULL out their arguments after
deleting them instead of doing it manually.

Closes #9685.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@64656 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/unix/net.cpp

@@ -236,8 +236,7 @@ wxDialUpManagerImpl::EnableAutoCheckOnlineStatus(size_t nSeconds)
    bool rc = m_timer->Start(nSeconds*1000);
    if(! rc)
    {
-      delete m_timer;
-      m_timer = NULL;
+      wxDELETE(m_timer);
    }
    return rc;
 }
@@ -247,8 +246,7 @@ wxDialUpManagerImpl::DisableAutoCheckOnlineStatus()
 {
    wxASSERT(m_timer != NULL);
    m_timer->Stop();
-   delete m_timer;
-   m_timer = NULL;
+   wxDELETE(m_timer);
 }