COFF associative sections is a feature where relocatable object files
can have section snippets marked as related to another section snippet,
so they are kept or discarded in relation to that other section snippet.
When llvm-objcopy removes sections, it also removes sections that are
marked as associative to the removed section (as the associative
sections otherwise would end up orphaned).
In a linked executable module (EXE or DLL), section associativity is
meaningless - thus, we should ignore those fields from the input.
After linking, GNU ld keeps the SectionDefinition auxillary part of
symbols intact as it was in the source object file, which means that it
references section numbers in the source object files.
This fixes https://github.com/llvm/llvm-project/issues/53433.
fcbbcffd2e