When linker relaxation is enabled, LoongArchAsmBackend may emit
relocations for same-section symbol differences, even when the fixup
is in a .dwo section. This leads to errors such as:
error: A dwo section may not contain relocations
Split DWARF (.dwo) sections must not contain relocations. Fix this by
resolving such fixups immediately when they are emitted into .dwo
sections, even if the referenced symbols are in relaxable sections.
This avoids generating invalid relocations in .debug_*.dwo sections
when compiling with -gsplit-dwarf and -mrelax.
Fixes#187428
89d8fe9d08