no error for bad page-height in tiffsave
no error for bad page-height in tiffsave

just don't write a toilet-roll image

the error was confusing and easy to trigger by mistake

see https://github.com/jcupitt/libvips/issues/782

jcupitt/libvips,lovell/libvips,lovell/libvips,lovell/libvips,lovell/libvips,jcupitt/libvips,jcupitt/libvips,jcupitt/libvips