Resync internal libgeotiff

git-svn-id: https://svn.osgeo.org/gdal/trunk@28238 f0d54148-0727-0410-94bb-9a71ac55c965
Add test for reading a GeoTIFF with both StdParallel1 and ScaleAtNatOrigin defined (#5791)

git-svn-id: https://svn.osgeo.org/gdal/trunk@28239 f0d54148-0727-0410-94bb-9a71ac55c965
Merge branch 'trunk' into trunk_travis_macosx