Update to ELF Tool Chain r3475

Improvements include:

• Add support for reporting and handling a number of new constants in various tools, including:
  • CloudABI OSABI
  • DT_TLSDESC_*
  • i386, MIPS, SPARC and amd64 relocations
• C++ demangler bug fixes
• Man page updates
• Improved input validation in several tools

This update also reduces diffs against upstream as a number of fixes
included in upstream were previously cherry-picked into FreeBSD.

Sponsored by: The FreeBSD Foundation