Fix adjustment of columns width in response to splitter position change in wPG.

In wxPropertyGridPageState::PropagateColSizeDec recursion is replaced with iteration and there is handled PG with more then 2 columns.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@78154 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775