Fix compilation on MinGW: cpl_vsi.h must be included before all other includes, so that VSIStatBufL is correctly set

git-svn-id: https://svn.osgeo.org/gdal/trunk/gdal@26355 f0d54148-0727-0410-94bb-9a71ac55c965
Windows CPLGetSymbol(): avoid dialog boxes to pop up when a DLL or one of its dependencies does not exist (#5211)

git-svn-id: https://svn.osgeo.org/gdal/trunk/gdal@26356 f0d54148-0727-0410-94bb-9a71ac55c965