[lld] [lld][ELF] Support LLVM repository and LLVM revision information (PR #97323)

[Hongyu Chen via llvm-commits]

yugier wrote:

> LGTM. The `After this change:` part in the description should be adjusted. The output is probably for LLVM_APPEND_VC_REV=on

I just did! Thank you for your fast response and help! :) 

https://github.com/llvm/llvm-project/pull/97323