Remove unused c code

[eivindjahren]

Removes unused c code now that only the python api and executables are considered public interface:

The current files that have been searched for unused c code

• lib/util/buffer.cpp
• lib/util/hash.cpp
• lib/util/path_stack.cpp
• lib/util/parser.cpp
• lib/util/statistics.cpp
• lib/util/cxx_string_util.cpp
• lib/util/util.cpp
• lib/util/util_opendir.cpp
• lib/util/lookup_table.cpp
• lib/util/util_unlink.cpp
• lib/util/node_ctype.cpp
• lib/util/string_util.cpp
• lib/util/path.cpp
• lib/util/util_lockf.cpp
• lib/util/perm_vector.cpp
• lib/util/util_symlink.cpp
• lib/util/hash_sll.cpp
• lib/util/util_abort.cpp
• lib/util/util_zlib.cpp
• lib/util/util_endian.cpp
• lib/util/node_data.cpp
• lib/util/test_work_area.cpp
• lib/util/util_spawn.cpp
• lib/util/mzran.cpp
• lib/util/util_getuid.cpp
• lib/util/test_util.cpp
• lib/util/rd_version.cpp
• lib/util/rng.cpp
• lib/util/stringlist.cpp
• lib/util/vector.cpp
• lib/util/hash_node.cpp
• lib/util/type_vector_functions.cpp
• lib/resdata/rd_util.cpp
• lib/resdata/rd_io_config.cpp
• lib/resdata/rd_sum_tstep.cpp
• lib/resdata/grid_dims.cpp
• lib/resdata/rd_kw_functions.cpp
• lib/resdata/rd_init_file.cpp
• lib/resdata/well_state.cpp
• lib/resdata/well_info.cpp
• lib/resdata/smspec_node.cpp
• lib/resdata/rd_rft_file.cpp
• lib/resdata/rd_grav_common.cpp
• lib/resdata/rd_rsthead.cpp
• lib/resdata/rd_region.cpp
• lib/resdata/rd_rft_cell.cpp
• lib/resdata/rd_file_kw.cpp
• lib/resdata/nnc_info.cpp
• lib/resdata/rd_rst_file.cpp
• lib/resdata/rd_box.cpp
• lib/resdata/rd_grid_dims.cpp
• lib/resdata/rd_sum_vector.cpp
• lib/resdata/rd_grid_cache.cpp
• lib/resdata/rd_kw.cpp
• lib/resdata/well_conn_collection.cpp
• lib/resdata/well_conn.cpp
• lib/resdata/well_segment_collection.cpp
• lib/resdata/rd_sum.cpp
• lib/resdata/RDFilename.cpp
• lib/resdata/rd_type_python.cpp
• lib/resdata/rd_nnc_geometry.cpp
• lib/resdata/rd_nnc_export.cpp
• lib/resdata/rd_coarse_cell.cpp
• lib/resdata/well_segment.cpp
• lib/resdata/rd_sum_index.cpp
• lib/resdata/nnc_vector.cpp
• lib/resdata/well_branch_collection.cpp
• lib/resdata/rd_sum_file_data.cpp
• lib/resdata/rd_subsidence.cpp
• lib/resdata/rd_unsmry_loader.cpp
• lib/resdata/well_ts.cpp
• lib/resdata/fault_block_layer.cpp
• lib/resdata/rd_type.cpp
• lib/resdata/FortIO.cpp
• lib/resdata/well_rseg_loader.cpp
• lib/resdata/rd_file_view.cpp
• lib/resdata/rd_file.cpp
• lib/resdata/rd_rft_node.cpp
• lib/resdata/fault_block.cpp
• lib/resdata/rd_smspec.cpp
• lib/resdata/rd_sum_data.cpp
• lib/resdata/layer.cpp
• lib/resdata/rd_grav.cpp
• lib/resdata/rd_nnc_data.cpp
• lib/resdata/rd_grid.cpp
• lib/resdata/rd_kw_grdecl.cpp
• lib/geometry/geo_region.cpp
• lib/geometry/geo_util.cpp
• lib/geometry/geo_polygon.cpp
• lib/geometry/geo_surface.cpp
• lib/geometry/geo_polygon_collection.cpp
• lib/geometry/geo_pointset.cpp
• applications/resdata/sum_write.cpp
• applications/resdata/view_summary.cpp
• applications/resdata/kw_extract.cpp