[llvm] [SystemZ][z/OS] TXT records in the GOFF reader (PR #74526)

[Kevin P. Neal via llvm-commits]

kpneal wrote:

Does this properly handle the case where the ED for some TXT records has a positive offset? In this case that offset should be subtracted from the offsets of LD symbols, TXT records that belong to that ED, and relocations into text belonging to that ED. Text at a negative offset is discarded. Relocation fixups at resulting negative offsets are discarded, though I haven't tested to see what happens if a relocation is partially negative.

https://github.com/llvm/llvm-project/pull/74526