Remove OGDIDataset::GetInternalHandle (#5779).

Fix error: cast to 'void *' from smaller integer type 'int'.


git-svn-id: https://svn.osgeo.org/gdal/trunk/gdal@28216 f0d54148-0727-0410-94bb-9a71ac55c965
GSpaceing is a BigInt, which is not always the same as an int and can cause an override mismatch.

git-svn-id: https://svn.osgeo.org/gdal/trunk/gdal@28217 f0d54148-0727-0410-94bb-9a71ac55c965
WCSDataset::DirectRasterIO psExtraArg argument is not used

git-svn-id: https://svn.osgeo.org/gdal/trunk/gdal@28218 f0d54148-0727-0410-94bb-9a71ac55c965