Use llvm objcopy and addr2line

[hlehser]

Since the tricore rust toolchain is based on the LLVM backend the tools objcopy and addr2line from the LLVM toolchain should be used
rename:

• objcopy -> llvm-objcopy
• addrline -> llvm-addr2line

[therealfrauholle]

This is a good idea especially for the windows setup, but we still want to keep compatibility with the normal GNU tools.

I suggest that we before invoking the command, we check for availability of the executables with <tool> --version, this allows us to support both tools.