[llvm] [Hexagon][llvm-objdump] Fix crash at a truncated instruction (PR #142082)

[Alexey Karyakin via llvm-commits]

quic-akaryaki wrote:

> `tools/llvm-dwarfdump/X86/debug_info_crel.yaml`

This test fails for me locally on the baseline commit too.

https://github.com/llvm/llvm-project/pull/142082