When generting DWARFv5 split dwarf macro info, debug_line_offset in
macro section header was pointing to debug_line_start symbol in .debug_line
section in primary binary resulting in relocation and subsequent
fatal error: error in backend: A dwo section may not contain relocations
In this case this should point to debug_line_start symbol in debug_line.dwo
section. LLVM does not emit debug_line.dwo section except for type
As of now skip this field emission, since it is optional.
Link to previous discussion: