[llvm] [BPF] fix print_btf.py test script on bigendian machines (PR #110332)

[via llvm-commits]

eddyz87 wrote:

@uweigand, could you please take a look? As far as I understand this has to land asap and I know that Yonghong is PTO today, and I need someone to review the change.

https://github.com/llvm/llvm-project/pull/110332