libelf_relocateadd() passes sym as NULL for a relocation against symbol
index 0, such as R_AARCH64_NONE. up_relocateadd() read sym->st_value
first, so loading a module with such a relocation faulted in the kernel.
Accept a NULL symbol for R_AARCH64_NONE and fail any other type, as the
other architectures do.
Assisted-by: Claude Code:claude-opus-5-5
Signed-off-by: Marco Casaroli <marco.casaroli@gmail.com>
3515e44845