don't use static buffer needing a critical section to protect it for logging; this...

don't use static buffer needing a critical section to protect it for logging; this results in deadlocks if the log sink decides to log itself (and this can be very difficult to prevent) and is unnecessary anyhow as the initial goal of allowing wxLog to work even for out of memory errors has never been tested and presumably never worked

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@40935 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775