Add support for big-endian RISC-V ELF files:
- Add riscv32be/riscv64be target architectures to Triple
- Support elf32-bigriscv and elf64-bigriscv output targets in
llvm-objcopy
- Update ELFObjectFile to handle BE RISC-V format strings and
architecture detection
- Add BE RISC-V support to RelocationResolver
- Add tests for new functionality
This is a subset of a bigger RISC-V big-endian support patch, containing
only the llvm-objcopy and libObject changes. Other changes will be added
later.
742147ba1b