diffoscope: use multitarget binutils

multitarget binutils is useful for diffing for directories with binaries
foreign to system where diffoscope runs.

before the change:

    $ nix run nixpkgs#diffoscope /tmp/a-Mcrt1.o /tmp/b-Mcrt1.o
    2022-07-27 21:20:35 E: diffoscope.comparators.elf: Command '['objdump --line-numbers --disassemble --demangle --reloc --no-show-raw-insn --section=.text {}']' returned non-zero exit status 1.
    2022-07-27 21:20:35 E: diffoscope.comparators.elf: Command '['objdump --disassemble --demangle --no-show-raw-insn --section=.text {}']' returned non-zero exit status 1.
    --- /tmp/a-Mcrt1.o
    +++ /tmp/b-Mcrt1.o
    ├── readelf --wide --decompress --string-dump=.debug_str {}
    ...

After the change:

    ./result/bin/diffoscope /tmp/a-Mcrt1.o /tmp/b-Mcrt1.o
    --- /tmp/a-Mcrt1.o
    +++ /tmp/b-Mcrt1.o
    ├── readelf --wide --decompress --string-dump=.debug_str {}
    ...

0 files changed, 0 insertions, 0 deletions