Add .gnu_hash support
Add .gnu_hash support

Almost all systems use .gnu_hash so implement it for tcc.
For most of them it is the default.

tccelf.c:
- Add functions elf_gnu_hash/create_gnu_hash/update_gnu_hash
- Update new_section/sort_sections/fill_dynamic/tcc_output_elf/elf_output_file

Tested with setting .hash section to SHF_PRIVATE in elf_output_file.

mirror/tinycc,mirror/tinycc,mirror/tinycc,mirror/tinycc